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Chapter 5: LightField First Light
Procedure
This chapter provides a step-by-step procedure for placing an imaging or spectroscopy
system in operation for the first time when using Princeton Instruments’ LightField 64-bit
data acquisition software. The intent of this procedure is to gain basic familiarity with the
operation of the system and to show that it is functioning properly. Once basic familiarity
has been established, then operation with other operating configurations, ones with more
complex timing modes, can be performed. This chapter assumes that the detector is being
operated with an IsoPlane SCT-320 spectrograph on which it has been properly installed.
REFERENCES:
Refer to Appendix C, IsoPlane 320 Mounting , on page 105 for
mounting instructions.
In a typical spectrograph, light enters the entrance slit and is collected by a collimating
mirror. Collimated light strikes the grating and is dispersed into individual wavelengths.
Each wavelength leaves the grating at a different angle and is reimaged by a focusing mirror
onto the exit focal plane. Essentially, a spectrograph forms an image of the entrance slit in
the exit focal plane with each position in the plane representing a different wavelength.
Since each wavelength falls at a different horizontal position, the spectrum of the input light
is spread across the array. Individual wavelengths focused at different horizontal positions
along the exit port of the spectrograph are detected simultaneously. Rotating the diffraction
grating scans wavelengths across the array, allowing the intensity at individual wavelengths
to be readily measured.
A suitable light source should be mounted in front of the spectrograph’s entrance slit.
CAUTION!
!
Overexposure Protection:
Detectors that are exposed to room
light or other continuous light sources quickly become
saturated. If the detector is mounted to a spectrograph, close
the entrance slit of the spectrograph to reduce incident light.