Optical Design

The instrument’s telescope design is monolithic (with no moving parts) and uses radiationtolerant glass lenses mounted in lens barrels. It is based on the SECCHI/HI design and consists of two telescopes, the inner and outer telescopes with the optical parameters shown in the table below. The optical layout is shown in the figure below (right side).

Mechanical Design

The WIM consists of a primary structure made from composite face sheets with a honeycomb core, which encloses two Focal Plane Assembly (FPAs) boxes, holding the detectors and detector readout boards (DRBs), two boxes for the baffles (interior and forward) and a plate for the peripheral baffle. In addition, the CIE is contained in a box attached to the rear of the primary structure and the radiators are mounted to the right side. The door mounts to the top and opens to the left.

Electrical Design

The WISPR electrical design builds upon the SoloHI development program and consists of two major components: the Camera Electronics (CE), provided by NRL, and the Instrument Data Processing Unit (IDPU), provided by the Johns Hopkins University/Applied Physics Laboratory (JHU/APL). Each component comprises several subsystems, which we describe briefly below.


The IDPU is mounted internal to the Parker Solar Probe (PSP), on the inside of the bulkhead to which the WIM is mounted. It is a two-slice assembly consisting of the Data Processing Unit (DPU) slice and the Low Voltage Power Supply (LVPS) slice enclosed in a Magnesium Alloy package (Fig. 22). The LVPS provides secondary power to the WIM and the DPU.