POM to FPA
NIRCam wheel (pupil)
NIRCam Mono OTE 03/02/04 Figure 3: NIRCam shortwave optical system.
PIL optics driving requirements
Once it was decided that a PIL was to be inserted into the short wavelength beam of the NIRCam instrument, a set of requirements was generated to define the performance of the optical system. A summary of the agreed upon driving requirements are listed in Table 1.
> 75% Strehl
> 1500 and < 2000 pixels
35 +0.0,-0.01 mm
Notes i.e. 1.87 microns ± 1%
Table 1: NIRCam Pupil imager optical specifications.
There were a number of basic optical design parameters for the PIL optics. The first design parameter was that the NIRCam PIL shall be designed to give an image of the primary mirror with a single star source within 10 arc-sec of the PIL boresight. The second design parameter was that the diameter for the PIL is set by the size of the unvignetted field. The third design parameter was the magnification of the PIL optics.