Reflector turret unit; S_M
Gear driven
For technicians and partly for sales managers!
These instructions describe the
procedures to install, adjust and exchange the gear driven Reflector Turret Unit (RTU) for Pannoramic SCAN and Pannoramic MIDI scanners. To help to
resolve problems with the turret unit or problems with fluorescent scanning, a
functional overview, hardware description of the used components and adjustment
procedures are added.
Contents
Construction
of the fluorescent exciting and image path
Mechanical components and construction
·
Diaphragm
position adjustment tools
·
Remove or mount the FL
reflector turret unit
Optical components
·
Light source adapter
and mounting
·
EPI-fluorescent
illumination unit
·
Mirror
Adjustments and checks
·
Tools, used for the
adjustments
·
Find the
first filter position
·
Adjust the aperture position
·
Adjust the aperture size
·
Adjust the Luminous field position
·
Adjust the luminous field size
·
Check the
correctness of the filter fixing in the filter positions
The reflector turret unit is
a component added to the Pannoramic SCAN
and Pannoramic MIDI scanners respectively to give the possibility for
fluorescent exciting and scanning of tissues. This component is not used for
bright field scanning. For fluorescent scanning of tissues, light color filters
are used in much variation. The filter wheel in this turret unit has ten
positions, so it can contain up to 9 light filters for fluorescent scanning. If bright field or fluorescent scanning is used, in
one filter position the turret tube must be inserted (default position =10). When the filters
are inserted, the user can select each filter (position) by software.
The instructions are shown for Pannoramic SCAN;
differences to Pannoramic MIDI are explained at the actual step. A significant
difference between Pannoramic SCAN and Pannoramic MIDI is, that the reflector
turret unit in the Pannoramic SCAN is mounted vertically during in the
Pannoramic MIDI it is mounted horizontally. This difference has no aspect in
functionality; the reflector turret units are identical.
The exchange of the
entire turret unit is possible
· If the stepper motor or
its electronics is faulty.
· If the shape of any part is deformed or a part is
broken.
· If the turret unit has any fault and you are unable to fix it.
Requirements
- Service
program for Pannoramic scanners (SlideScanner Service.exe) with actual license file
- Pannoramic SCAN and Pannoramic Viewer software
(SlideScanner.exe, SlideViewer.exe) with actual license file
- 1.5, 2.5, 3 and
- Hardware and construction knowledge of Pannoramic
SCAN
and MIDI
respectively
- Deeper knowledge of handling the Pannoramic SCAN
and Pannoramic VIEWER software
Attention: Do not mix the versions of SlideScanner.exe and
SlideScannerService.exe! Always use these programs with the same version
number. Otherwise the SlideScanner Service.exe program could produce unwanted
results and SlideScanner.exe does not work correctly or even freeze!
Functional overview
Construction of the fluorescent exciting and image path
The
fluorescent light source is connected to the turret unit via the „Fluorescent light
source adapter mounting”; the adapter itself is used to interfacing the
traditional light source like the „X-Cite® Series 120” or the “Lumencor®”
exciting light source. The
tissue is stained and prepared to fluoresce, if it is excited with a high
intensity light. The emitted light beam of the light source is prepared by the
“Aperture stop diaphragm” and the “Luminous field stop diaphragm”.
The mirror reflects the light beam to the excitation
filter of the “Filter block”.
In the filter block the excitation filter, the beam
splitter and the emission filter are combined for a special excitation and the
relevant emission wave length.
The appropriate wave length of the excitation light
beam passes thru the excitation filter and will be reflected to the objective
by the help of the beam splitter.
The optics in the objective is used to illuminate the
tissue and excites the used stain of the field of view.
The stain of the tissue fluoresces and the emitted
light rays (in a higher wave length then the excitation wave length; with less
brightness) are collected by the objective; the image passes thru the beam
splitter, the emission filter and the tube lens to the CCD of the scan camera.
The wave lengths of the components (the excitation
light wave length, the characteristics of the filter block and the used stain of
the tissue) are combined for a specified light wave length; this must be met by
all used components, otherwise the quality of the scanned tissue is reduced or
even bad.
See also: “Optical path and
Field Of View”
See also: “Influence of the camera adapter” and “Useable resolutions of scan (main)
cameras”
Traditionally,
the fluorescent light beam may contain all the wavelengths from ultra violet
(from about 320nm) thru the visible light (about 400nm to 720nm) until the
infra red spectrum (over 720nm to 1000nm). The relevant wavelength to excite
the stain (fluorophore) of the tissue is filtered and passes thru the
excitation filter; all other wavelengths will be reflected by the exciting
filter. In other words, the characteristic of the excitation filter defines the
light wave length to excite the stained tissue.
The filtered wavelength will be reflected to the
objective by the beam splitter and so the fluorophore in the field of view of
the tissue will be illuminated (excited).
Important
The characteristic of the excitation filter and the
beam splitter must meet the exciting wavelength of the fluorophore!
In newer exciting light sources like the Lumencor® Spectra, the exciting light will be
generated by power Illumination modules which produce the exciting light wavelength
directly. By switching the Exciting modules and using multi band filters,
combined for more wavelengths in the same filter block (e.g. Quad Band Filters), the
movement of the filter wheel can be reduced to a minimum and so the fluorescent
scan procedure is less time consuming.
See also: “X-Cite®
Series 120Q”, “Xcite®120PC_UserGuide”,
“Filter block”, “Lumencor® Spectra”, “Determining
the Filter Type” (Semrock)
1 Fluorescent light input
connector
5 Mirror
10 RTU motor
13 Flexible
shaft for the position adjustment bolts
Components of the fluorescent RTU
The stepper motor is
used to rotate the filter wheel of the turret unit and so, any inserted filter
(or filter position) can be selected via software commands at the appropriate moment.
- The motor is driven in micro steps; the
revolution of the rotor is divided into 3200steps.
- The stepper motor of the gear driven
reflector turret unit gets its commands via the bus cable STF-4.
- The address of
the motor electronics is 06.
- The stepper motor is mounted to the turret
plate via the “Mounting nuts”.
The gearwheel on the motor axle drives the filter wheel
via the transmission gear. The mechanical drive solution allows a filter
position change with exact 6400 motor steps. In other words, the motor axle
does exact two revolutions to reach the next or previous filter position. To
move the filter wheel from the first position to the 10th position
the wheel goes 9 positions forward, i.e. the motor axle does 18 revolutions to
reach the last filter position.
·
By loosening the transmission gear
mounting and moving it away from the motor axle, the filter wheel disconnects
also from the transmission gear and so the position of the limiter in relation
to the transmission gear can be modified; the required hardware limit position
can be found.
The Filter
wheel has 10 positions, so it is able to contain up to 9 filters and the
fluorescent tube for the brightfield scan procedure. The filter blocks are
fixed in their positions via springs. For bright field scanning and fluorescent
scanning also, in the 10th filter
position the image path cover tube must be inserted, or at least no filter
block must be inserted in this position.
The filter
fixing springs are very sensitive in question of deforming, because these
springs guarantees the proper position of the filter block in relation to the
optical axis.
Any improper
fixing of the filter in the filter wheel (some 10th mm are
important) modifies the “1st filter position” of
the incorrect inserted filter block and so the straightness of the optical axis
is also incorrect; this results in improper exciting of the stained tissue and
reduced image scan quality of the virtual tissue; see also Check the filter block
positions.
- Keep the position
surfaces of the filter block and the filter wheel clean and dry.
- During insertion or
removal of the filter block take care on the filter fixing springs; do the
action carefully, without deforming the springs.
Insert or remove filter blocks
Fit
the filter block between the springs, into the filter block position of the
filter wheel as shown, then press the upper edge carefully downward until the
sideward pressing springs fixing the filter block correctly.
Check the proper
position of the filter block in the filter wheel manually; movements on the
position surface must not occur.
- During the removal of the filter block, the
springs on the top must not be deformed!
To avoid miscounting of steps a mechanical limiter is
mounted on the filter wheel (the filter wheel would be able to rotate endless,
but the sensor home 2 finds the home position of the mechanical construction
only inside a limited number of rotor revolutions). This way, the mechanical
construction has a start point (negative mechanical limit) and an end point
(positive mechanical limit). The limiter is mounted between two filter
positions so, that both filter positions can be reached; these are the mechanical
first and the mechanical last filter position (not the 1st and the
10th filter position). If the limiter is mounted in wrong position
(if it is mounted on the neighbor bolt), the limits can not be adjusted
correctly! The negative limit is not, and must not be identical with the home
position! The size of the limiter and its mounting position guarantees, that no
motor steps are lost, if the adjustment of the mechanical drive was done
correctly. The distance between the first filter position and the 10th
filter position is always exactly 57600 motor steps!
· The size of the limiter is designed to fulfill the
Home 1 limit of the stepper motor.
See also: “How to
define hardware limits”, “Stepper motor
implementation”, and “Construction of Home1 and
Home2”
Because a limiter is mounted on the
drive part of the filter wheel, the mechanical movement has a negative and a
positive limit.
· The accuracy of the hardware limits is 100steps
The number of steps from the home
position to the first filter position (about +300 steps) can differ by a few
hundred steps.
See also: “How to
define hardware limits”,
The
adjustment bolts are used in a pair of bolts with a shorter
and a longer flexible shaft and these adjust the position of the
aperture and the luminous field diaphragm respectively in X- and Y-direction
in relation to the light beam. The fixing bolt is also used to bearing the tool
knob in the mounting. The fixing bolts for the other two tool knobs are found
on the opposite side, from the top. By removing the fixing bolt the appropriate
adjustment bolt can be dismounted, if necessary.
Handling the position adjustment tools
Loosen the
“Aperture size” and / or the “Luminous field size” tool knob fixing.- Loosen the
appropriate position tool knob fixing bolt(s).
- Rotate the
tool knob(s) until the desired position is reached.
- Tighten the
tool knob fixing bolt(s) to fix the adjusted position.
Iris size
adjustment tool
With
the adjustment tools “Aperture size” and “Luminous field size” the size of the iris
can be defined via an ex-center. This transforms the up and down movement of
the “Aperture size” or “Luminous field size” tool respectively to a rotation of
the iris mechanics and this will more open or more close the iris.
Both tools can be fixed separately by screwing the
tool knob.
If the spring was dismounted or is not fixed properly,
there exists the possibility that the ex-center is disconnected from the bolt
of the iris mechanics. In this case, you are unable to adjust the iris size.
Check the connection between ex-center and iris bolt always after reassembling.
If the open and close tool is fully pulled or fully pushed, disconnection must
not occur. Check this behavior in various end positions of the adjustment bolts
also!
Handling the size
adjustment tools
- Loosen the tool knob fixing.
Move the tool knob up or down until the
desired size of the aperture or the luminous field respectively is found.- Tighten the tool knob fixing.
Check mechanical
shutter closed position
During a fluorescent FOV is visible on the
screen (as live view) switch on and off the bright field illumination
several times with the service program. If the shutter is in proper position
the brightness of the view must not change.
See also: “Focus unit’, and “Shutter mechanics”
Remove the RTU (SCAN)
1.
Remove the camera tube (if exchange).
2.
Remove the
cable STF-4 (if SCAN) from the turret
stepper motor.
3.
Remove or
loosen respectively the mounting bolts for the turret unit as shown.
4.
Pull the entire
fluorescent reflector turret unit in an angle of approximately 30 degrees to
your self and upward.
Insert and mount the RTU (SCAN)
1.
Insert the new reflector turret unit.
2.
Tighten the
bolts in the sequence from 1 to 4 as shown.
3.
Connect the
turret stepper motor cable STF-4.
4.
Insert the
camera tube.
After the turret unit was changed, the
adjustments described above should be checked and the appropriate parameters of
the file “MicroscopeConfiguration.ini” sections [ReflectorTurret] and [Hardware
Limits] must be updated, and the file must be saved. In all cases the chromatic aberration
and the camera angle
must be adjusted; see also “Stitching”.
Remove the RTU (MIDI )
1.
Remove the camera tube (if exchange).
2.
Remove the
cable for the turret motor STG-4 (not
shown).
3.
Remove or loosen
respectively the mounting bolts for the turret unit as shown.
4.
Remove the
supporter mounting bolt; hold the turret unit, remove the supporter tube
carefully and then pull the entire unit as shown.
Attention! The turret unit
is heavy!
Insert
and mount RTU (MIDI)
1.
Mount the turret unit in reverse order as it was
dismounted.
2. Insert the turret unit, underpin it with the supporter
tube and mount the supporter mounting bolt. The turret unit should be fully inserted
(without a gap to the main truss)!
3.
Mount the clamp
to the main truss and then tighten the bolts in the shown sequence.
4.
Connect the
cable STG-4
to the turret stepper motor.
5.
Finally insert
the camera tube.
After the
turret unit was changed, the adjustments described above should be checked and
the appropriate parameters of the file “MicroscopeConfiguration.ini” sections [ReflectorTurret] and [Hardware Limits] must
be updated, and the file must be saved. In all cases the chromatic aberration
and the camera angle
must be adjusted; see also “Stitching”.
Components and construction of fluorescent optics
The
flexible light guide of the excitation light source is connected by the help of
the collimating adaptor to the light source connector.
· To
reach an evenly exciting of the field of view, the flexible light guide should
be guided straight about 30cm before it arrives to the collimating adapter.
· 
To
avoid loss of brightness, the light guide must be fully inserted into the
collimating adaptor and, the light guide must be fully inserted on the lamp
side also.
· Never
bend the flexible light guide excessive!
See also: “X-cite120PC_UserGuide”, chapter
7 and chapter 8
EPI-fluorescent illumination
unit
The aperture stop (a metal device that
limits the amount of light going through the system), the luminous field stop
(a metal device that limits the area of the visible field) and the condenser (a
lens that serves to concentrate light from the exciting source that is in turn
focused through the object) are situated on the “EPI-Fluorescent
illumination unit”. The mechanical construction of the aperture stop and
the luminous field stop is identical.
Position
of the diaphragm
The
diaphragm of the aperture stop and the luminous field stop are forced upward by
a spring. By driving the adjustment bolts in or out a limited movement in the
X- and Y-direction of the diaphragm can be performed; so the iris will be
centered in relation to the beam. Very important in this construction is the
force of the spring. If the force of the spring is too low (the spring is not
inserted well or mechanical jamming between diaphragm and housing occurs) the
diaphragm can not be adjusted or only in a very small range. If there is any
problem with positioning the diaphragm, check the easy movement of the
diaphragm manually, the proper position of the spring and the drive mechanics
of the adjustment bolts.
Take into account, that the “Aperture size” or the
“Luminous Field size” tool respectively can prevent the appropriate diaphragm
from movement, even if it’s fixing is tightened!
By loosening
the fixing bolts on both sides of the condenser the focus position can be
adjusted by moving it toward or away respectively from the luminous field stop.
The condenser is mounted perpendicular to the fluorescent light beam. If the
condenser’s focus is reached, a sharp view of the iris of the luminous field
stop is visible on the live view even if the luminous field size is smaller
then the image size of the camera.
§
Keep the lens surfaces of the condenser clean
See also: “Cleaning optics” and Condenser
Mirror
The
mirror is mounted at an angle of 45 degrees to the light beam and reflects the
excitation light to the filter block.
Filter
block
The filter
sets for fluorescent scan
exist in various filter combinations
to filter the light of a specific wavelength to excite the fluorescent stain of
the tissue (Excitation
filter) and to filter the relevant, emitted light of the stained tissue
(Emission filter). The beam splitter reflects the shorter light wavelength
during the light with the longer wavelength passes thru it. The filter sets are
assembled to a filter
block or filter cube. The wavelength varies in the range between ultra violet excitation (350 nm) -
blue emission (450 nm) and orange excitation (600 nm) - deep red
emission (690 nm). A wide
spectrum of filter sets ör blocks is available from major microscope
manufacturers via
product number. If you are self assembling the filter set into a block, take
care on the positions where the filters are mounted. The Emission filter shows
always to the camera and the Excitation filter to the fluorescent light source.
The Excitation filter, the Emission filter and the Beam splitter are combined
for a special light wave length and therefore they must not be mixed with parts
of another set!
See also:
·
„Filter
block”; Zeiss filter
·
“Matching
Fluorescent Probes with Nikon Fluorescence Filter Blocks”; interactive
·
‘Introduction
to Fluorescence Filters” (Semrock)
· “Setup filters” (to
assign colors, color channels, and filter positions)
See also: “Optical path and Field Of View”
When the
filter block is inserted properly into the reflector turret filter wheel,
the springs are fixing the filter block in its position and no further
adjustments are needed.
The “hole” in the filter block (opening without
filter) shows always to the objective.
The
fluorescent cover tube does not contain optics, it is always used in the 10th filter position of the filter wheel;
it covers the image path and is inserted or mounted like a filter block.
Virtual tissue
To
allow analyzing of parts in the tissue (e.g. nuclei, or DNS fractions), parts
can be stained with special stain. A
wide range of fluorescent stains (fluorophores) is available for different
markers. Each stain is excited by a special wave length of the excitation light
and emits light in another, relevant wavelength. One tissue can be stained with
more than only one stain (fluorophore), so different parts of the tissue can be
visualized in different colors at the same time.
To reduce the exposure time of the camera and to
produce a high quality of the virtual fluorescence tissue, the used filter
block must match the excitation wavelength (the source wave length to excite
the stain) AND the emission wavelength (the emitted wavelength of the stain)
also. Furthermore, the emitted wavelength of the exciting light source must be
able to excite the stain in its wavelength.
To produce a high quality of the virtual fluorescent
tissue and to reduce the exposure time during fluoresce scan the following
parameters are very important:
1) The characteristic of the exciting
light source (emitted wave lengths)
2) The characteristic of the used
filter block (exciting and emission wave length) and
3) The characteristic of the used
stain (exciting and emitted wave length).
The best virtual tissue quality (and the shortest
exposure time also) will be reached if all the characteristics are optimal met,
otherwise the exposure time will rise up and the virtual tissue becomes more
poor.
If the wave lengths of one component differ too much,
the scanned quality is very poor or even bad!!
More information about Fluorescence
Microscopy!
- Keep the surface of the cover slip and the surface of the slide
bottom clean; see also: “Cleaning optics”
Autocollimator
An autocollimator is an optical instrument for non-contact measurement of angles. They are typically used to
align components and measure deflections in optical or mechanical systems. An
autocollimator works by projecting an image onto a target mirror, and
measuring the deflection of the returned image against a display with a scale,
either visually or by means of an electronic detector. A visual autocollimator
can measure angles as small as 0.5 arc seconds.
The dovetail ring adaptor is used to interface the
autocollimator and the check camera to the light source adaptor.
For
adjustments, a green filter block is necessary. Nevertheless, the finished
adjustments should be checked with the filter set of the user.
· The light
source is used to illuminate the stained tissue during the fluorescent scan
process. Depending on the light source, found by the user, the X-cite® type
light engine or the Lumencor SPECTRA light engine® is used to define the
luminous field size.
Precautions
Never look directly into the beam of the fluorescent light
source! The lamp emits also ultraviolet light with very high intensity. To
prevent your eyes from harm (damage) use always sun glasses with a high filter
factor of UV light if the fluorescent light source is switched on and you are
adjusting the beam even if the cover of the turret unit is removed. For further
precautions please, refer to the manual for the fluorescent light source you
are using!
· This
type of light sources generates all exciting wave lengths at the same time; a
white light beam is created. With this light source only single band filters
can be used.
See also: “X-Cite
Series 120Q” and “Xcite120PC_UserGuide”
Lumencor
SPECTRA light engine®
Never look directly into the beam of the fluorescent
light source! For further precautions please, refer to the manual for the
fluorescent light source you are using!
· This
light source generates monochromatic exciting wave lengths; the desired wave length
can be selected by software. With this light source single band or multi band
filters can be used likewise.
See also: “Lumencor
SPECTRA light engine®”
Check camera (optional)
The
check camera (VRmc-8+ PRO)
and the objective (TAMRON 23FM16SP),
together with the auxiliary illumination it is used to make the position and
the size of the aperture stop iris visible; adjustment details are visible on
the screen.
· The
mounting with a dovetail ring adaptor allows the use of the check camera for
the PMIDI and the PSCAN type scanners also.
Requirements
To make the aperture iris visible on the screen by the
use of this camera “VRmagic”, the “VRmagic Cam Lab” is required!
Setup in the software version 1.16 VRmUsbCam
DevKit for Windows (x86) 3.15b.msi
Setup in the software version 1.15 VRmagic
USB Camera Development Kit 3.13g.msi
· The
camera uses an USB 2.0 port, otherwise, if the transfer rate of 280Mb/s can not
be reached (USB1.1 or lower), the camera window will disappear automatically
after some seconds, without any notice!!
Check
camera mounted
Mount
the check camera onto the X-Cite® type adapter and connect it to any USB 2.0
port. Memorize the serial number of the camera.
See also: “Preview camera VRmagic” and “Program
CamLab”
Adjust filter wheel and
mechanical drive
The relevant adjustment is done by
positioning the connection of the transmission gear wheel in relation to the
limiter of the filter wheel, while the stepper motor is in Home1,2 position.
This adjustment should be done:
- If the home positions Home1 and Home2 (with the
service program, Low Level Service) cannot be reached.
- If motor steps are lost during Home1 and Home2
will be reached.
- If moving to the last filter position causes lost
motor steps (check the backlash).
- If moving to any filter position causes lost
motor steps (check the backlash).
- If the gear bolt was loosened
- If the stepper motor
had been exchanged
If an error of this type named above
occurs please, switch off the power supply and remove all the filters from the filter
wheel. If any filter is inserted wrong (upside down or not correctly) this
behavior can occur also. Check also for unwanted or unexpected mechanical parts
inside the turret unit which can inhibit the wheel from movement. After all
filters are removed check the mechanical drive again with the Low Level Service
part of the service program. Check the home positions Home1 and Home2; check
the negative turret limit, the backlash in each filter position and the
positive turret limit, and compare them with the appropriate parameters of the
file “MicroscopeConfiguration.ini” sections [HardwareLimits] and
[ReflectorTurret].
Define
hardware limits
1.
Loosen the gear bolt and move it downward, so that there
is no connection between motor axle and filter wheel, the gear is disconnected.
Check the easy and soundless movement of the filter wheel manually!
2.
Start the
program SlideScannerService.exe and Low Level Service.
3.
Switch active
the section “Reflector turret” and press Home1 and Home2 for “Filter”.
4.
If motor
movement stops and the home positions Home1 and Home2 are not reached, press
Home1 and Home2 for “Filter” again until the home positions are reached (it can
take a minute, depending from the actual position).
5.
Bring the
filter position 6 to the top, insert a small piece of paper or aluminum foil
between the cogs of the gear wheel and the filter wheel, connect the gear (move
the gear bolt upward) and tighten the gear bolt so that there are about 3 cogs
distance exists between the gear wheel and the limiter. The small piece of
paper between the cogs of the gear wheel and the filter wheel helps to reach a
small backlash (about
Adjust the negative
turret limit
6.
Press Home1 and Home2 again.
7.
With the “-100
steps” button go to the negative limit until the filter wheel movement stops,
jamming occurred or -1500 steps are reached. If the position of -1500 steps is
reached press Home1 and Home2, loosen the gear bolt, repeat step 5 meanwhile
decreasing the number of cogs in distance to the limiter by 2. If the reached
step value without jamming (subtract in mind 100 steps of the shown value if
jamming occurred) is between 300 and 600 steps the adjustment is O.K. If the
step value is less then 300 steps, increase the distance to the limiter by 1
cog. If the step value is more then 600 steps, decrease the distance to the
limiter by 1 cog. Repeat steps number 6 and 7 until the negative limit is found
correctly.
8.
The correct
negative limit is found if: -600 steps ≤ negative limiter ≤ -300 steps, without mechanical jamming. Update the
parameter value of the parameter “ReflectorTurretMin” with the found value in
the file “MicroscopeConfiguration.ini”
section [HardwareLimits].
Backlash of the filter positions
9.
Go forward from
filter position to filter position 9 times and check the backlash manually in
each filter position. A very little backlash should exist (less then a half cog
in distance) in each filter position. Listen also to the wheels movement sound.
If there can be recognized a sound of mechanical jamming or in a filter
position is no backlash, increase the backlash by loosening the gear bolt,
moving it carefully downward a little bit and tighten it again. Repeat this
step until the size of the backlash is acceptable.
Find the step
number for the first filter position
10. The best way, to find the first filter position is the
use of an autocollimator.
If you don’t have an autocollimator, you can adjust the first filter position
as described in the following step, the results are acceptable also. For the
adjustment procedure with the use of an autocollimator please refer to the
chapter “Autocollimator”
after this adjustment procedure and step 9 of this procedure can be left out.
Press Home1 and Home2.
The position,
where a filter can be inserted is now the position 6, the position one is
exactly in opposite position, in the light path.
a.
Possibility:
In this position insert the turret tube and place a spirit level on it.
With the service program go forward by +100 steps until the level is reached.
For fine adjustment you can use a step size of 50 steps. Use the found value to
update the value of the parameter “StartingMotor Position” of the file “Microscope
Configuration.ini” section [ReflectorTurret] and save the file. An exact
fine adjustment of the first filter position is done later, if the fluorescent
light path will be adjusted.
· Take into account, that the spirit level has a
tolerance of almost 20%; so the result will not be exact. If possible, please
adjust the first filter position always with an autocollimator; see also: “Autocollimator”.
b.
Possibility, if you have no spirit level or the
adjustment is done for Pannoramic MIDI:
It is recommended to do this adjustment before optical adjustments are
done, otherwise the camera
rotation angle must be adjusted again.
Dismount the camera tube and look inside the hole. With the service
program go forward by +100 steps from Home1 and Home2 until the hole of the
turret filter wheel is in the center of the mounting of the camera tube. For
fine adjustment you can use a step rate of 50 steps. Use the found value to update the value of
the parameter “StartingMotorPosition” of the file “Microscope
Configuration.ini” section [ReflectorTurret] and save the file. An exact
fine adjustment of the first filter position is done later, if the fluorescent
light path will be adjusted.
· Take into account, that the used method is not
precise; so the result will not be exact. If possible, please adjust the first
filter position always with an autocollimator; see also: “Autocollimator”.
To adjust the
positive limit
11. Starting from the last filter position check the
number of steps, until the positive limit is reached. There should be at least
+300 steps until jamming, but not more then 59100 steps absolute in relation to
Home1 and Home2, otherwise do the entire adjustment again from step one. Check
also the position of the limiter. If it is mounted in wrong position, the
limits can not be reached correctly. The correct positive limit is found if:
Last filter position +300 steps ≤ positive limiter ≤ +59100 steps absolute, in relation to Hom1,
Home2; without mechanical jamming. Update
the value of the parameter “ReflectorTurretMax” with the found value in the file
“Microscope Configuration.ini” section [HardwareLimits] and save the file.
Finally
12. Test the adjustment. Calculate and type in the number
of motor steps to test the reflector turret unit from Home1,2 to the last filter
position; the number of steps is found as follows: Number of steps for the
first filter position + 57600 (9x6400). Move the filter wheel from Home1,2 to
the last filter position and this number of motor steps return with the
unnumbered blue arrow buttons for reflector turret “Filter” to Home1,2, but do
not press Home1,2.
Execute
the test forward and backward with the defined number of steps, then press
Home1. If the adjustment is correct, there should not be more then 1 or 2 steps
difference to Home1,2. Now press Home2 and do this test three times. If there
are more then 2 steps lost, check the backlash and the adjustment again. Do not
forget to remove the piece of paper or foil.
Autocollimator
An autocollimator
is an optical instrument for non-contact measurement
of angles.
They are typically used to align components and measure deflections
in optical or mechanical systems. An autocollimator works by projecting an
image onto a target mirror,
and measuring the deflection of the returned image against a display with a
scale, either visually or by means of an electronic detector. A visual
autocollimator can measure angles as small as 0.5 arc seconds.
Attention: Do not forget to remove the fluorescent shutter from the
fluorescent light path; otherwise the filter wheel position can not be
adjusted.
Check or find the 1st filter position
- This adjustment assumes that the belt tightness is adjusted
correctly.
- The
acting range of the external sensor is found; the Home1,2 position of
the filter wheel is correct.
To
find the first filter position
A. Mount the
autocollimator with the dovetail ring adapter to the fluorescent light input
connector and switch it on with the highest intensity.
B. Press
Home 1 and Home 2.
C. After
the filter is inserted, bring the filter into the light path by pressing 5
times the button 6400 forward for the turret filter unit.
D. With
the 100 steps button go forward or backward until the LASER beam appears on the
scale.
E. Select
a step size of 10 steps and find the center of the scale by pressing the button
without step number.
F. By
reducing the intensity of the laser beam the reached position can be checked
better; see “Centered 2”.
G. If the
center is reached, subtract 32000 from the Filter step number (because we moved
the filter wheel 5x6400steps forward) shown for the turret unit and use the
found value to update the value of the parameter “StartingMotorPosition” of the
file “MicroscopeConfiguration.ini” section [ReflectorTurret] and save the file.
H. Switch
off the autocollimator and dismount the dove tail ring adaptor.
Fluorescent light and image
path
Precautions: Never look directly into the beam of the fluorescent
light source! The lamp emits also ultraviolet light with very high intensity.
To prevent your eyes from harm (damage) use always sun glasses with a high
filter factor of UV light if the fluorescent light source is switched on and
you are adjusting the beam even if the cover of the turret unit is removed. For
further precautions please, refer to the manual for the fluorescent light
source you are using!
FL Aperture
The
aperture diaphragm illuminated with the fluorescent light source.
If the cover of the turret unit is removed, you can
see the beam on the iris, if this is not fully opened.
With the “Aperture positioning tools” bring the iris
into the centre of the beam. Check the position by varying the aperture size
tool. The center of the beam is reached, if the cut part of the beam is
illuminating the aperture iris evenly.
To
adjust the aperture if the cover is mounted, you can use the bright field
illumination.
Insert a sample, open the mechanical shutter, bring
the filter block into its position and switch on the bright field illumination.
· In the
P250 please use any kind of auxiliary illumination; the flash frequency of the
flash light source is too slow in the service program.
If you
are looking now into the “Fluorescent light source connector” and the luminous
field size aperture is fully open, you can see the aperture of the objective
and by moving the aperture open or close tool you see the position of the
aperture iris. Adjust the iris position to the centre of the beam. By carefully
varying the size of the aperture, you can check the behavior of the iris. The
movement should be even in all directions related do the center of the beam.
· Adjust
the aperture size so, that the aperture of the objective is evenly not cut.
If the
cover is removed and you are looking onto the luminous field diaphragm on the mirror
side during adjustments, some times you can see that the reflected beam
(reflected by the filter block) does not meet the hole of the iris. In these
cases, may be the filter position is not correct (if the reflected spot is up
or down in relation to the iris and no autocollimator was used; see the image
on the right) and / or the position of the luminous field diaphragm is
incorrect (if the reflected spot is on the left or on the right in relation to
the iris).
Check the position of the “Luminous field size
diaphragm” next.
In
ideal cases you can see somewhat like this. The field size is in the center;
the filter block position is correct and the luminous field diaphragm is
centered; the reflected spot illuminates the edge of the iris hole evenly.
Adjustments, checks
Check
or adjust the aperture diaphragm position
Loosen
the fixing bolt of the aperture size.
Before you start to adjust the aperture position or
the field position, the fixing of the “Aperture size” or “Luminous field size”
tool respectively should be loosened, otherwise it blocks the diaphragm
movement, because the force of the spring is not enough to move the iris.
Check
or adjust the luminous field stop position
The check of the luminous field stop position is done
as described in the chapter “Check the
filter block positions”
Prepare
the FOV for the adjustment
4. With
the program SlideScanner.exe
produce a live view with the option bright field scanning and the tab “Focus”.
The tissue type can be a “normal” tissue, it is not important that the tissue is
not prepared for fluorescent scanning (only the exposure time for the camera
must be increased more!).
5. Use a
well visible FOV where the corners of the FOV have tissue also. This becomes
important if we adjust the field size. Adjust the focus position and memorize
it.
6. Kill
the program “SlideScanner.exe” with the task manager.
Prepare
the turret unit for the optics adjustment
7. Start
“SlideScannerService.exe” and “Low Level Service”.
8. Switch
active the service part for “Reflector turret” and “Focus” and press Home1 and
Home2 for “Filter” and “Focus”.
9. Go to
the first filter position; the value of steps is given by the parameter
“StartingMotor Position” of the file “MicroscopeConfiguration.ini” section
[ReflectorTurret]. In position 6 of the turret wheel insert the filter block
and go forward 5 positions. If all is correct, the numerical value in the field
“Filter” of the service program shows the sum of 32000 (5 times 6400 steps) +
the value of the parameter “StartingMotorPosition”.
10. In the
“Focus” part of the service program close the shutter; use the value of
“FocusDeviceMax” in the file “Microscope Configuration.ini” section
[HardwareLimits].
11. Open
the aperture intensity and luminous field size to maximum. Start the driver
program for the marlin camera “AVT SmartView,exe” and increase the shutter in
the dialog “camera settings” until the FOV becomes visible. In the menu “View”
select the option “resize the picture to the screen”. Now go backward with the
focus stepper (do not press Home1 or Home2!) from the focus position
“FocusDeviceMax” to the memorized, actual focus position. The FOV or a part of
it should be seen in focus and the mechanical shutter stays closed. Switch off
the bright field illumination. Adjust the shutter value for the camera and the
focus position so, that the illumination and the focus of the FOV is correct.
Adjust
the aperture position
14. Prepare
a sample for bright field illumination, insert the filter block and bring it in
the fluorescent scan position. If the fluorescent light source is disconnected,
you can see a light spot and the aperture iris in the light source connector.
The right aperture position is found if the beam is in the centre of the
aperture iris. The adjustment is done with the “aperture position” tools. You
can check it by observing the iris in relation to the objective aperture. By
carefully opening or closing the size of the aperture, you can check the
behavior of the iris. The movement should be evenly in all directions related
do the center of the beam. Tighten the fixing for the tool bolts.
Remember, that
the “Aperture intensity” tool can deform the result of the position; therefore,
during adjustment the intensity tool should be moved up or down from time to
time, at least, before the adjustment seems to be finished.
Adjust the luminous field position
15. The
right “Luminous field position” is found if the beam is in the centre of the
luminous field iris. The adjustment is done with the “Luminous field position” tools. You can check
it by observing the iris pupil in relation to the beam. You can see the
reflected light of the beam from the condenser side. If the pupil border is
evenly illuminated by the beam, the adjustment is finished. You can see the
tissue in the centre of the screen, if the luminous field size is nearly closed.
Now open it
carefully until the screen border is reached by the tissue and check the
luminous field position again. If the position is correct, the not illuminated
parts in the corners should be equal in size. A fine adjustment of the luminous
field position can be done now, if necessary. Tighten the fixing for the tool bolts.
Remember, that
the “Luminous field size” tool can deform the result of the field position;
therefore, during adjusting the field position, the field size tool should be
moved up or down from time to time, at least, before the adjustment seems to be
finished.
Check the filter block positions
·
For
correct exciting of the FOV during fluorescent scan the insertion of the
filters in all used positions should be checked or adjusted.
·
For this check use always the same filter
cube in each position of the filter wheel.
·
During this checks, the field size
diaphragm should be fully closed.
1. Start
the scan program “SlideScanner.exe”.
2. Select
“Microscope settings” in the menu “Options”.
3. Connect
and switch on the fluorescent light source.
4. In the
tab “Base Settings” (1) select the desired filter position; e.g. “Position 1” (2).
5. Insert
the filter cube into the filter wheel, position 1.
6. Check
“Enable position” (3).
7. Set
the radio button “Fluorescent” (4).
8. Select
the tab “Camera Rotation” (5).
9. Load a
Magazine (6) and insert a slide with (any) tissue (7) (in the first filter
position only).
10. Check
“Live view” (8).
11. Find a
FOV inside the tissue and adjust the focus position (9) (in the first filter position
only).
12. Set
the “Auto Expo”sure time (10) (in the first filter position only).
13. Close
the tool “Field size”; only a small circle should be seen, nearly in the middle
of the red cross.
Remark: If the deviation
of the filter block axis in relation to the optical axis is very much, may be
you can not see the tissue (the screen is fully black). In such cases open the
luminous field size until the tissue becomes visible. Adjust the filter
position parts as described in “To reduce
the deviation from the center” then close the tool “Field size”
again. Repeat this procedure, until the
center of the red cross is met inside the tissue and the tool “Field
size” is fully closed.
14. Make a
screenshot with “Print Screen” and save it; e.g. with “Irfan view”; the file
name should be the filter position.
15. Switch off the live view, go
back with the tab “Base settings” (11) and remove the filter cube.
16. Select
the next filter position; e.g. “Position 2”,
insert the filter and repeat from step 6 logically.
17. Execute
the screenshots in all (desired) filter positions.
18. Analyze
the “Print screens”.
If the center of
the red cross can be found always inside the tissue, the filter cubes are
inserted well and no further adjustments are needed.
The screenshots
on the right show acceptable deviations from the center.
A real result of
the adjustment can also be found in the slide show: “Filter
positions”
The field size of
the luminous field is set to the minimum. Because the tissue is visible in the
center (shown with the red cross) of each filter position, the adjustment is
acceptable, but the position of the field diaphragm might be adjusted a bit
more precise.
Reduce
the deviation from the center
There are 4 possibilities to reduce the elongation of the
luminous field from the center of the red cross:
1.
Check the
backlash of the filter wheel; the tightness of the belt.
2.
Adjust the
luminous field stop position in the filter positions 2, 5 and 8, find the
optimum and check always the correct insertion of the filter block in the named
positions also.
3.
Check and adjust the value for the first
filter position more precise.
4.
Increase
the pressure of the springs carefully for the filter block mounting in these
filter positions, where the deviation from the center is too much.
Adjust
the luminous field size
·
Increase
the luminous field size until the entire screen is filled with tissue. Stop the
adjustment and tighten the luminous field size tool. For best results the
adjustment should be done two or three times.
·
Check the correct field size after all
filters are inserted; the seen FOV must not be cut.
Adjust
the aperture
Close fully the aperture intensity tool
then open it carefully until the brightness is not increased more. Stop the
adjustment and tighten the tool fixing. For best results the adjustment
should be done two or three times.
Check
the shutter closed position
While a fluorescent FOV is visible on the screen
(as live view) switch on and off the bright field illumination several
times with the service program. If the shutter is in proper position the
brightness of the view must not change.