WFIRST Instrument Reference Information (Cycle 7)

The optical reference information files are gradually being updated as Phase A progresses. Files with dates prior to September 2017 are based on the "Cycle 6"point design for the WFIRST Observatory, which was the design presented at the Mission Concept Review, held on December 8-9, 2015. The files with later dates or version numbers indicating Cycle 7 incorporate changes that have been made over the course of Phase A. The changes in the optical design since the start of Phase A are generally small, so the files that are not yet updated are still useful.

WFIRST Instrument Field of View Layout,  Sky Projection Phase-A Design
The Wide-Field Instrument

» WFIRST Wide-Field Instrument Reference Information (.pptx) A compendium of basic reference information on the WFIRST Wide-Field Instrument, June 14, 2017

Point-spread functions

Point-spread functions for the WFIRST Wide-Field Instrument (aka 'Wide Field Camera') can be computed at any wavelength and at any position in the field of view, given knowledge of the pupil function. The following files give Zernike decompositions of the wavefront error and pupil masks needed to perform this calculation.
» WFIRST MCR: Data from WIM Model (.xlsm) Contains the Zernike coefficients for the WFI, and also provides a fit to distortions in WFI imaging mode (WIM), a mapping of WIM detector positions onto the sky, WFI SCA positions in the focal plane, etc. Zernike coefficients are also provided for the grism Wide-Field Spectroscopy Mode (WSM) in first order, and for a single field position in 0th and 2nd order.
» WFIRST MCR Wide Field Channel PSF-Zernike Cross-check (.ppt)
» Explanation of Zernike coefficients (.docx)

Integral Field Channel (IFC)

» WFIRST MCR Integral Field Channel Simulated Wavefront Data (.xlsx) Similar wavefront error information for the Integral Field Channel (IFC) is provided, for two locations in the optical path: the image slicer and the detector surface. WFE information at the slit mirrors is not yet available. The IFC resolving power vs. wavelength tables are included in one of the tabs in this spreadsheet.

» Sample PSF calculations for the IFC (.xlsx) The ordering of the tabulated PSF data in this file is the same as for a displayed image: the first row in the table corresponds to the top of the image, and the first column corresponds to the left edge of the image, etc.


» WFIRST (MCR Design) Exit Pupil Masks for the Wide Field Instrument (.pptx) This describes the orientation of the pupils, and includes other relevant information.


» Wide Field Instrument Throughput Model (.xlsm) This spreadsheet gives the effective area for the wide-field imager through each filter and through the grism, and for both IFC channels.

» Grism Mode SCA Projected Fields (.xlsx) This spreadsheet provides a calculator for each SCA giving the mapping in both directions between sky angle and wavelength to detector position.

WFIRST Instrument Reference Information Archive Pages

Cycle 6 | Cycle 5

Goddard Space Flight Center