P09052 Molecular Imaging System Upgrade

Transcription

1 P0905 Molecular Imaging System Upgrade Table of Contents Conference Paper Calibration Procedure.. 7 Depth Calculation. Calibration Results.. 4 Depth Results.. 5 Recommendations. 7 Drawings. 9

2 Calibration Procedure: Test Setup: Place 0 transparencies taped together (or other suitable non-glossy surface) onto platen, and place top on Imaging System. Housing for grid adjustment should be removed until grid has been focused onto image plane. Excitation filters were not used during calibration procedure. Ensure that the Imaging System and the Optigrid motor control are connected to the Imaging Computer. Phase : Scheimpflug djustments - To bring the Optigrid into focus on the image plane with maximum contrast. Manually adjust the lens linear stage along the optical rail to achieve desired image distance.. For Computar C lens setups, position the Optigrid plane approximately cm from the center of the lens.. Manually adjust the lens and Optigrid fixtures until grid lines can be seen on the platen. 4. Using the linear and rotary micrometers, finely focus the grid onto the platen. a. Using the preview feature of the Kodak MI software can help during focusing of the Optigrid Phase : Optigrid Polarization Procedure - To establish consistent phase movements of Optigrid before calibration begins. Ensure US connection to Optigrid motor control is connected to PC, and power on motor control unit.. Start US Demo pp.6. Polarize the Optigrid by entering 0 in the left Phase Voltage region and 40 in the right Phase Voltage region. 4. Click test start. This will toggle the Optigrid phase between 0 and 40 V. 5. Let this run for 0 minutes. 6. djust Grid Voltage to 0 V by entering '0' into the 'Grid Voltage' dialog box on the Optigrid US Demo pp.6 and clicking 'Set Grid Voltage'. of 0.

3 Figure. US Demo pp.6 Phase : Coarse Calibration - To determine approximate voltage ranges for 0 and 40 degree phase shifts. Set camera to desired settings. Sample settings used during prototype calibration can be seen below.. Minimizing ambient light to the system, take image with specified setting at 0 V of grid voltage.. Export data as an 6 bit TIF with no scaling. File Export Image, Save as Type '6-bit TIFF File-No Scaling(*.tif) Use file name 0.tif 4. Repeat steps and in 5 V increments up to and including 0 V, accumulating 7 images 5. Start MTL and change the current directory to location where images are saved. Save a copy of calcphase.m to this directory. 6. Run calcphasenew.m. The output is a phase versus voltage plot. 7. efore running the code, a portion of the image must be selected that shows high contrast and minimal distortion. The code will rotate the image a set amount and must be adjusted to each set of calibration images. of 0.

4 Figure : Sample Camera Settings for Calibration Procedure 7. From the plot determine center voltages for fine calibration. Select a voltage to remain static during fine calibration. 0 V and 0 V are the recommended.. Record the phase at this voltage. dd 0 degrees to the phase.. Locate the two voltages which the new phase lies between. Calculate the approximate 0 phase location using: 4. dd 40 degrees to the phase at chosen static voltage. Repeat step to determine voltage for 40 degree phase shift. 4 of 0.

5 X: 50 Y: Figure. Sample Phase vs. Voltage plot (Output of Coarse Calibration Phase 4: Fine Calibration. Keeping the same camera settings the same as fine calibration.. Select a range of plus or minus volts from the three selected voltages determined in coarse calibration. a. For example, if 0 V, 68 V and 9 V are determined to be the phases separated by 0 o, voltages of 0 V, 65 7 V and V would be selected.. Create a test plan to showing the sequence of captures. test plan for the above example is shown in Figure Capture an image at each location. It is EXTREMELY important the grid be moved in the following matter: a. First LWYS start the grid at 0 V. Then move to the first voltage (0 V) and capture and image. Label this image V_. Then move to the next voltage (65 V) and capture another image. Label this image V_. Then to the next voltage (88 V). Label this image (V_). Then, the grid must be brought back to 0 V before moving back to the next line (0 V). Label this image (V_) and continue on through the entire plan. The naming convention for the files is: Phase _ Image Set Number.tif Where Phase is either V, V or V. 5.Open of CalcOG.m. Change the number of iteration of the for-loop to the number of image sets. 6. Run the code. This will calculate all of the combined images. 7. Open MMeritMap.m. Change the path names in line 8 and 0 to the location of the images. 5 of 0.

6 Image Set Number Phase Voltage (V) Phase Voltage (V) Phase Voltage (V) Figure 4. Sample Test Plan 6 of 0.

7 8. Change the variables V_coarse and V_coarse to reflect the voltages that were used in the test. For this example, Vcoarse= 65::7 and V_coarse=88::9. 9. Run the code and a merit map will be generated. sample Merit Map is shown in Figure 5 0. The images with the lowest score will have the best phase separation and those voltages should be used when acquiring images Fig. 5 Sample Merit Map. 7 of 0.

8 Depth Calculation: When three phase-shifted images are captured depth information can be extracted from an image. This is accomplished by monitoring each individual points. When a point of an object is captured with three different phase the intensity over those three phases will model that of a sine curve. (see Figure 6). s the source of the intensity moves away from the platen the magnitude of the sine wave decreases. Therefore, depth can be calculated based on the magnitude of the best fit sine wave of the three points. Fitting a sine wave can be difficult so anther correlative property is that of the mean squared error with respect to the mean of the three points. Where m(i,j) is the mean of I,I and I at the location (i,j) Fig 7. High mplitude phase shifted data (Upper Left) nd their corresponding points plotted on a sine curve (Lower Left). Low mplitude phase shifted data (Upper Right) nd their corresponding points plotted on a sine curve (Lower Right). 8 of 0.

9 Calibration Results: Many attempts were made at calibrating the Optigrid. These are the best results that we could attain and the results corresponding to them. The voltages selected were 0 V, V and 7. V. It can be observed that the lines are completely gone in the combined image (Figure #) when compared to the image captured at 0 V (Figure #). Figure # Structured Illumination picture at 0 V 9 of 0.

10 Figure #. Resulting Combined Image. Depth Results: When depth resolution was performed on the following image (Figure #) Figure # resulted. The image capture used minute exposure times. 0 of 0.

11 Figure # Original Image that depth analysis is performed on. Figure #. Depth Estimation of calibration block of 0.

12 Recommendations: ngle djustment: The rail angle adjustment was not tested in the experiments. The steepest angle supported by the system was used for all of the results presented. This helped reduce distortion associated with projection angle. There is a trade off between maximum magnification and maximum angle. s the magnification is increased, the projection angle with respect to the platen is decreased. For the presented prototype, it was deemed more important to have a greater range of magnification. For future testing, it may be beneficial to investigate using a shorter rail with a smaller magnification range. utomation: There are two areas of the presented system whose performance would be greatly enhanced by automation: Optigrid Calibration and Optigrid Warm-Up. Calibration of the Optigrid often requires over 00 images to be taken. Using the current methodology, even with relatively low exposure time, this process is very time consuming and prone to human error. Timing is also very critical to achieving repeatable phase shifts in the Optigrid. utomation of this process would cut down on calibration time and improve on timing consistency. Resulting in more consistent and accurate results. Ensuring the Optigrid is conditioned properly for repeatable results requires the Optigrid to be warmed up and constantly exercised before use. The current motor control allows for the cycling of grid voltage value between values. Modification of this GUI to allow for more voltage values to be included in this cycling would allow for a warm up routine which would better mimic the phase shifting seen during image capture further increasing repeatability of system performance. Integration of the Optigrid motor control GUI into the image capture software proved to be beyond the scope of this project. Establishing communication between these two programs would be the first step in achieving integration, and would help automate the above mentioned processes. Calibration Procedure Modifications: possible way to increase the performance of the Optigrid would be to take four phase separated images at 90o apart rather than three images 0o apart. This could help reduce any of the first harmonic that may reside in the combined image. It also may prove to be more forgiving in that more images would be subtracted possibly canceling out some data that would result from an imperfectly shifted image. dditionally, a fourth point would increase the accuracy of the estimation of the magnitude of the illumination when considering depth. Instead of starting the calibration process at 0 V, starting at 0 V should be considered. The piezo actuator is more linear in the central portions of its region of movement and this shift would move the target voltages more in the linear range. This is important because it decreases the penalty for not having perfectly shifted images. of 0.

13 Mechanical Modifications: dding another clamp to the enclosure would help to keep out more stray light. The current clamp only hold down one side. Putting a shorter optical rail in the box could increase the angle of projection which would cause there to be less distortion. However there would be a trade off in that the range of motion along the rail would be diminished. of 0.

14 4 DRWN Patricia 5//009 CHECKED RIT & Carestream Q TITLE MFG ox Extension Notes: ) Extension Material:.09" Mild Steel ) eroglaze Z06 Flat, diffused black paint (Sherwin Williams UT-J6 black powder coat recommended) 4 PPROVED SIZE SCLE DWG NO oxextension SHEET OF 5 REV 4 of 0.

15 4 Left Extension Right Ledge Flat lank.75 (.000) R (45 ) Right Ledge Formed (.798) (X) R.09 DRWN Patricia 5//009 CHECKED RIT & Carestream Q TITLE MFG ox Extension PPROVED 4 SIZE SCLE DWG NO oxextension SHEET OF 5 REV 5 of 0.

16 4 45 R.50 Right Side Flat lank ase Flat lank ase Formed 0.7 Right Side Formed R (.500) DRWN Patricia 5//009 CHECKED RIT & Carestream Q TITLE 0.75 MFG PPROVED ox Extension 4 R.09 (.500) SIZE SCLE DWG NO oxextension SHEET OF 5 REV 6 of 0.

17 Cover Flat lank.000 Top Flat lank R Top Formed R Cover Formed 7.75 (.548) R.09 (0.76) DRWN Patricia 5//009 CHECKED Q TITLE RIT & Carestream R.09 MFG ox Extension PPROVED SIZE SCLE DWG NO oxextension SHEET 4 OF 5 REV 7 of 0.

18 4 ssembly Weld Joint Top Left Extension Right Ledge Welded Joint to ox Right Side Weld Joint Weld Joint to ox Weld Joint to ox Cover ase Weld Joint DRWN Patricia 5//009 CHECKED RIT & Carestream Q TITLE MFG ox Extension PPROVED 4 SIZE SCLE DWG NO oxextension SHEET 5 OF 5 REV 8 of 0.

19 4 D Drill and Tap for /4-0 SHCS 0.6 [.400].00 [.000] 8.55 [.50] 45. [5.78] 9.70 [7.587] 7.66 [8.569] [.76] [.600] D.00 [.000] 0.6 [.400] [0.000] 5. [.056] (58.57 [.06]) (R6.5 [.50]) (87.64 [.450]) 6.5 [.50]. [.48] (.69 [5.4]) [.746] [4.5] 44.6 [5.680] C (57.5 ) 6.69 [8.5].5 [8.800] (9.87 [9.050]) 7.49 [9.50] C 5.40 [6.000] [.500] (64.97 [6.495]).09 [8.50] (8.44 [8.600]) 6.50 [.500] Drill and Tap for a 0- Screw 05.8 [4.45] 76.0 [.000] 5.40 [6.000] 47. [.855].5 [5.50] 9.05 [.750] 5.40 [6.000] DRWN Patricia 4/8/009 CHECKED Carestream-RIT Q TITLE MFG L-racket Notes: ) Material: ase:.5" luminium Side:.75" luminium 4 PPROVED SIZE C SCLE DWG NO Lracket SHEET OF 9 of 0. REV -

20 4 DRWN Patricia Heneka 5//009 CHECKED RIT & Carestream Q TITLE MFG Phantom lock Notes: ) Material: /" Lexan (Polycarbonate) ) Size: 0 sheets of 5x8 plastic with (4) /4" holes.5" from the edge ) Hardware: (4) /4-0.5" Screw and /4-0 Nut 4 PPROVED SIZE SCLE DWG NO Phantomlock SHEET OF REV 0 of 0.