Cary 500 Procedure

Cary 500 Procedure

Written by: Jessica D’Amico

Instrument Warm-up

1. Start Cary 500 Dell computer.

2. Open Cary WinUV icon.

3. Open Align. (Wait until the Align window appears before going on to next step.)

4. Turn on Cary 500 (switch on front left of instrument)

5. Allow Align to go through warm-up process, ending with the numbers at the top of the window turning red (or “Idle” flashing in bottom left of Align window). (Suggested: Allow the Cary one half hour to warm-up prior to making measurements.)

6. Return to WinUV window. (Do not close Align window.)

7. Open Scan program.

8. Press “Connect.”

9. Go to File > Open Method.

10. Open C:\Varian\Methods\Standard_Reflectance.MSW if starting with reflectance measurements. Or open C:\Varian\Methods\Standard_Transmittance.MSW if starting with transmittance measurements.

Reflectance Measurements (With Integrating Sphere)

1. File > Open Method. Open C:\Varian\Methods\Standard_Reflectance or follow steps 2 through 5.

2. Press the Setup button on the left side of Scan window.

3. Under the “Cary” tab check that the X mode is in nanometers from desired range (usually 2500nm to 350nm).

4. Under the Y mode change the mode to %R and set the scale from 0 to 100.

5. Under the “Baseline” tab select the radio button for Baseline Correction. Press “OK.”

6. Open green Cary lid and check that curved mirror is in %R position. (Follow alignment instructions on Page 4 to check or alter alignment). The %R position is with the curved mirror closest to the integrating sphere, %T position is with the mirror farthest away from the sphere.)

7. Close green Cary lid.

8. Check to make sure Spectralon is in front sample port (with gray curved holder in place) and sample port is securely closed. (Figure 3) NOTE: Make sure writing on the Spectralon disk used is right-side up to ensure disk is in the same position and orientation each time it is scanned.

9. Press “Baseline” button on left side of Scan window. (This runs the 100% T baseline, press “OK”).

10. With Spectralon in place and baseline collected, press “Start” button to collect a white reference.

11. When asked where to save the file to be collected, create a new folder in C:/Cary 500 Data with today’s date. (For example, July 23, 2003 would be 20030723).

12. Open the folder and save the white reference scan as “whtref_1.” When asked for a sample name, the same filename can be entered. (White reference scans are done with the standard reference Spectralon in the reflectance port.)

13. NOTE: You may want to press the rulers button (two rulers forming a right angle) in the Scan window and change the y-axis values to 99-101 nanometers to get a better look at the white reference. If the white reference scan contains large “steps,” or is not close to flat, perform a 100%T Baseline followed by another white reference scan.

14. Open sample port and remove Spectralon and gray holder. (WEAR GLOVES when handling Spectralon!)

15. Place Spectralon in black holder face down on top of Cary.

16. Put sample to be measured in sample port, pressed firmly against the circular hole. (Figure 2) Use ring to ensure sample is flat (clear tape may be used to flatten or hold sample in place. Make sure tape is not visible on area of sample to be measured.)

17. Close sample port.

18. Press “Start” button, and save file with descriptive name (sample1_ref_front). Save the sample as the same name as the file.

19. Continue to measure sample reflectance (both front and back of samples) as desired.

Dark Scans ( 0% T Baseline Scans) for Reflectance – currently not used 20040405

* 0% baseline scans are performed very rarely in reflectance mode, as it is difficult to do so with the main lab area lights on (as light leaks through the cracks between the door and the wall). However, when necessary, follow the steps below. *

1. Open the 2nm SBW - 1nm Sampling.MSW method in C:\Varian\Methods. This method allows for both a 100% T baseline and a 0% baseline. (Check to make sure the setup parameters are in %R mode and measuring within the desired wavelength range. See Reflectance Measurements for specifics.)

2. For reflectance, perform the standard 100 %T baseline with the Spectralon in the sample port. (See instructions for Reflectance Measurements.)

3. Move the mouse to the “OK” on the window that starts the 0% baseline but DO NOT press “OK” until steps 4 through 12 have been completed.

4. After 100% T baseline is completed, open sample port and carefully remove Spectralon disk and rounded, gray plastic holder. (USE GLOVES when handling Spectralon!) Place the Spectralon face down in the black case on top of the Cary.

5. Keep sample port open, with no sample in place.

6. Check to make sure all items around the front of the Cary have been removed and that the path between the opened sample port and the gray laboratory wall is clear.

7. Remove any other especially white or shiny materials from the Cary bench area.

8. Carefully cover the green light from the Cary’s on switch and gently wrap a cloth around the Cary’s underside lighting to prevent this light from interfering with the dark scan measurement. DO NOT cover the vents on the Cary tightly or for an extended period of time. Use the cloth only to block the light and remove it promptly when the dark scan is completed.

9. Turn off or cover all other system lights in the area or laboratory. Make sure all monitors are off, num lock and caps lock buttons are deselected on all keyboards, CD drive lights are covered, and speakers are off. Place another cloth in the crack between the door and the floor.

10. Turn room lights off.

11. If you have not moved the mouse since step 3, pressing the left mouse button once will start the 0% baseline scan. If this does not work, turn the monitor on, realign the mouse with the “OK” button and turn the monitor off. Allow 30 seconds before clicking the mouse and starting the scan.

12. Once dark scan is completed, you may turn on all monitors and room lights and continue standard measurements.

Transmittance Measurements

*Follow same procedure when handling Spectralon and running white reference as done with reflectance measurements. *

1. File > Open Method. Open C:\Varian\Methods\Standard_Transmittance.MSW (or follow steps 2 through 5 below).

2. Press Setup button at left of Scan window.

3. Check X mode to ensure instrument is set for nanometers and the scale is 2500nm to 350nm (unless instructed otherwise).

4. Change Y Mode to %T and set scale from 0 to 100.

5. Under the “Baseline” tab select the radio button for Baseline Correction.

6. Check that mirror is in %T position. (The %T position is with the curved mirror farthest away from the sphere.)

7. Check alignment. (Follow alignment instructions below to check or alter alignment).

8. Close green Cary lid.

9. Press Baseline in left of Scan window. This runs the 100% Baseline, press “OK.”

10. With Spectralon in place and baseline collected, press “Start” button to collect a white reference.

11. When asked where to save the file to be collected, create a new folder in C:/Cary 500 Data with today’s date. (For example, July 23, 2003 would be 20030723).

12. Open the folder and save the white reference scan as “whtref_1.” When asked for a sample name, the same filename can be entered. (White reference scans are done with the standard reference Spectralon in the reflectance port.)

13. After the white reference scan has been collected, open green Cary lid and place sample to be measured in sample transmittance holder (located in the back of integrating sphere).

14. Close green Cary lid.

15. Press Start, record file name (sample1_trans_front) and sample name.

16. Continue to measure sample transmittance (both front and back of samples) as desired.

Dark Scans ( 0% T Baseline Scans) for Transmittance

*Note: Room lights do not need to be off for 0% baseline in transmittance mode as a metal plate is used to block the beam. *

1. Open the 2nm SBW - 1nm Sampling.MSW method in C:\Varian]Methods. This method allows for both a 100% T baseline and a 0% baseline. (Change the setup parameters are in %T mode and measuring within the desired wavelength range. See Transmittance Measurements for specifics.)

2. Perform the standard 100 %T baseline with the Spectralon in the reflectance sample port and the transmittance sample holder empty. (See instructions for Transmittance Measurements.)

3. Open the long (leftmost) drawer under Cary and take out thin black metal plate (typically stored in the left side of the drawer)

4. After 100% T baseline is completed, open green Cary lid and gently place metal plate inside the Cary against the transmittance sample port. Set the plate on the floor of the machine and rest it so it is angled slightly towards the integrating sphere. Be careful and DO NOT allow plate to touch optics.

5. Close the green Cary lid.

6. Keep Spectralon disk in reflectance sample port and keep port closed.

7. Press “OK” to begin 0% T baseline scan.

Adjusting Mirrors

1. Open the green Cary lid.

2. Gently loosen the leftmost knob on the curved mirror. (This allows you to lift and reposition the mirror as needed.)

3. Hold the mirror steady by the top knobs and carefully slide it to the desired position (“R” for reflectance or “T” for transmittance).

4. The leftmost loosening knob will fit into left hole in each position, and the adjustment knobs (middle and right) will fit in the right.

5. After the mirror has been placed in desired position tighten the leftmost knob.

6. Check alignment. (Page 4)

Additional Mirror Adjustments

* When the curved mirror is moved from position R for reflectance to position T for transmittance the beam no longer hits the center of the bolted mirror in the left corner of the instrument alongside the integrating sphere. (This is part of the reason the 100% T baseline in transmittance is so low.) However, the bolted mirror need not be adjusted for every measurement and should therefore only be altered when it is absolutely necessary and then only with the help of a supervisor. *

1. Open green Cary lid.

2. In Scan press “F4” and enter “555” to select green for the beam color.

3. Check alignment. (See Checking Alignment section for specifics.)

4. Use the large flathead screwdriver to slightly loosen screw attaching small mirror in the corner to the left of the integrating sphere. LOOSEN SCREW ONLY SLIGHTLY as mirror does not need to be lifted or repositioned, just rotated a very small amount.

5. Gently rotate the bolted mirror until the green beam can be seen in the center of the curved mirror.

6. Once mirror is aligned properly gently tighten the screw at its base.

7. Close green Cary lid and proceed with measurements.

* Note: Remember to check alignment any time the curved mirror is moved and remember to adjust the bolted mirror again after switching modes if it has been rotated. *

Checking Alignment

1. In Scan, Press “F4” (or go to Commands > GoTo) and enter “555.” (This sets the beam wavelength to green, allowing the user to see the beam and adjust alignment.)

2. For reflectance remove Spectralon panel at top of integrating sphere and look inside at the sample Spectralon. The green beam should be crescent shaped and in the center of the sample port.

3. For transmittance place a white business card in the transmittance sample holder at the back of the integrating sphere (Figure 6). The green beam should be a small crescent and in the center of the transmittance sample port area.

4. If the beam is not centered in either case, gently turn the middle knob on the curved mirror (Figure 5) to move the beam up and down and use the right knob to move the mirror right and left. (After the mirror has been positioned do not adjust the leftmost knob! This knob is used for mirror removal and installation as it loosens and tightens the mirror setting.)

5. Return to step #7 in Reflectance Measurements (with Integrating Sphere) or step #8 in Transmittance Measurements.

To Remove Integrating Sphere

1. POWER OFF!!! Turn off switch on left front side of Cary (green light will be off.)

2. Open green Cary lid.

3. Carefully remove connector from green center plug. (Figure 5) NOTE: Be careful not to let power cords touch the mirrors, it will scratch them..

4. Loosen two (2) screws (back of capture area) with knurled ends using long Phillips head screwdriver. BE CAREFUL NOT TO TOUCH OPTICS!

5. Lift up sphere (carefully) by black handle and gently rock up and down to free it.

6. Once loose, slide sphere straight out holding black handle. (Do not lift the sphere by the mirrors!)

7. Remove two (2) pins used to hold sphere in place. (After sphere is removed these pins will stick up in the front). DO NOT LOSE THESE PINS! (Place pins in empty black Spectralon holder in drawer under Cary when not in use.)

8. When removing sphere for validation test purposes DO NOT insert the cuvette holders. For transmission measurements place cuvette holder pins into drilled holes.

9. Install front Cary panel. (Lift panel slightly above Cary side height and gently slide panel into place.)

10. Close green Cary lid.

11. Turn power on (front left switch on Cary).

12. Place black integrating sphere cover over mirrors and gently screw down into place.

To Install Integrating Sphere

1. POWER OFF!!! Turn off switch on left front side of Cary (green light will be off.)