Princeton Instruments HRS-300, Operating Instructions Manual

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18
C. Focusing and Alignment of Array Detectors
With the array detector properly mounted to the HRS-300, use the following procedure to align and focus
the array detector to the HRS-300 optical system. It assumes that the array detector is mounted to the
HRS-300 and running for the following procedure.
1. Mount a light source such as a mercury pen-ray type to the entrance slit of the HRS-
300. PI offers a standard Mercury/Neon-Argon lamp, IntelliCal, designed for this
purpose. Any light source with line output can be used for focus. If there are no “line”
sources available, it is possible to use a broadband source such as tungsten for the
alignment. If this is the situation, use a wavelength setting of 0.0nm for alignment
purposes.
2. With the HRS-300 properly connected to the computer, turn the power ON and move the
spectrograph to a wavelength of 546.074nm if using a mercury lamp, or 0.0 nm for a
broadband source, or another wavelength corresponding to a known peak produced by
another “line” source.
3. With the array detector operating, check the image of the light source if running in
an imaging mode with a CCD. Otherwise check the line intensity and shape.
4. Using a 9/64
th
Allen wrench, loosen the split clamp screw approximately ½-turn and
slowly slide the array detector IN or OUT until the sharpest image is achieved, or the
sharpest line is achieved. There is a focus stop thumb wheel screw included at each exit
port to assist in fine focus adjustments as well as rotational alignment of the camera to
the HRS-300.
5. Move the thumb wheel until it just makes contact with the array detector mounting flange.
This enables you to rotate the detector without changing the focus position. Rotate the
detector for correct alignment of the slit image to the CCD. Optional LightField software
includes an “align spectrometer” function for this purpose. The thumb wheel
adjustments may be used to precisely position the detector - one eighth of a turn of the
thumb wheel changes the detector position by approximately 1/10th of a millimeter.
6. After each adjustment, ensure the array detector mounting flange is in contact with the
thumb wheel. Tighten the split clamp to secure the detector in position when sharpest
focus has been achieved.
7. The light source can be removed if desired and replaced by fiber optics or other light sources.
8. If fibers or other imaging optics are used to bring light into the HRS-300, they may
require adjustment along the optical axis to achieve best vertical image qualit