entrance slit

entrance slit

[′en·trəns ‚slit]
(spectroscopy)
Narrow slit through which passes the light entering a spectrometer.
References in periodicals archive ?
The spectrometer accepts light from the solar corona along a long, narrow entrance slit and during the eclipse, this slit scans to observe the whole corona.
The spectral integrated energy received by a spectrometer's exit slit can be regarded as the slit's response to the superposition of all the shifted monochromatic images of entrance slit [3, 13].
A custom, multireflective entrance slit plate provides a unique arrangement of nine different slit gaps, ranging from 20 to 100 microns, and three pinholes that you can quickly select using a built-in thumbwheel.
The standard NIRQiest512-1.9 comes with a 150 lines/mm grating, 25micron entrance slit and a non-fluorescing longpass filter that transmits >1000nm.
A fiber-optic bundle carries light from the image plane to the entrance slit of the spectrometer.
lb show the geometric relationship between the entrance slit, the grating, and the exit slit in a scanning spectrometer and a spectrometer with a CCD array detector respectively.
It was built in a mahogany housing for stability and had an adjustable width entrance slit, a 20-cm focal length quartz collimating lens, a Comu quartz prism, a 20-cm quartz camera lens and a plate holder for a 3.25 x 4in.
Depending on the user-selected configuration of grating options and optical bench entrance slit size, optical resolution as good as 4.1 nm to 6.3 nm (FWHM) is possible.
A second eyepiece "sees" the field of view around the spectrograph's entrance slit and works with autoguiders for long-exposure imaging.
For a collimated or narrow-angle source, this is not a problem, because the light can be focused onto the entrance slit, but for tissue, not only is the light source spatially large, it also has a large angular spread.
Briefly, a Ni-coated toroidal mirror collects 20 mrad horizontally and the full vertical extent of the emission from SURF III and focuses the radiation onto an entrance slit. The radiation is deflected and refocused by a second toroid and is incident on one of two gratings: a 600 [mm.sup.-1] grating blazed for 20 nm, which we operate between 8 nm and 40 nm, or a 1500 [mm.sup.-1] grating blazed for 8 nm, which we use from 3 nm to 14 nm.
The spectrometer should be able to connect the optical fiber on entrance slit.