Table 8. Spectrograph Adapters - Princeton Instruments PI-MAX 3 System Manual

Table of Contents

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Hint: Overhead fluorescent lights produce a mercury spectrum. Use a white card

tilted at 45 degrees in front of the entrance slit to reflect overhead light into the

spectrograph. Select 435.833 as the spectral line.

3. Set the slit to 25 µm. If necessary, readjust the SuperSYNCHRO frequency to

maintain optimum (near full-scale) signal intensity.

4. Slowly move the detector in and out of focus. You should see the spectral line go

from broad to narrow and back to broad. Leave the detector set for the narrowest

achievable line.

Note that the way focusing is accomplished depends on the spectrograph, as follows.

5. Next adjust the rotation. You can do this by rotating the detector while watching a

live display of the line. The line will go from broad to narrow and back to broad.

Leave the detector rotation set for the narrowest achievable line.

Alternatively, take an image, display the horizontal and vertical cursor bars, and

compare the vertical bar to the line shape on the screen. Rotate the detector until the

line shape on the screen is parallel with the vertical bar.

Note: When aligning other accessories, such as fibers, lenses, optical fiber adapters, first

align the spectrograph to the slit. Then align the accessory without disturbing the detector

position. The procedure is identical to that used to focus the spectrograph (i.e., do the

focus and alignment operations while watching a live image).

PI-MAX



Long focal-length spectrographs such as the Acton SP-2300i: The

mounting adapter includes a tube that slides inside another tube to move the

detector in or out as required to achieve optimum focus.



Short focal-length spectrographs: there is generally a focusing mechanism

on the spectrograph itself which, when adjusted, will move the optics as

required to achieve proper focus.



No focusing adjustment: If there is no focusing adjustment, either provided

by the spectrograph or by the mounting hardware, then the only recourse will

be to adjust the spectrograph's focusing mirror or to shim the detector.

Spectrograph

Acton

Chromex 250 IS

ISA HR 320

ISA HR 640

SPEX 270M

SPEX 500M

SPEX TripleMate