Grid Mounting Instructions for SPARO

Below is a description of how to mount a polarizing grid onto the front of SPARO's snout for calibration purposes. A discussion of integration times needed when doing grid tests can be found in Giles' E-mail

The test grid used on SPARO is a gold colored rectangle which is 50 mm x 70 mm. It should be located in a plexiglass holder(with some masking tape on it)in the SPARO closet. It is either on one of the shelves or in the red toolbox where other optics are kept. Be careful when handling it as it can freely slide out of the plexiglass and the wires are fragile.

The grid is mounted on the front of SPARO's snout at approximately a 45 degree angle as shown in the first image below. Two custom retainer clips are used to mount the grid and do so by exerting pressure on the sides of the grid. These clips are attached to SPARO's snout already. To install the grid, place it between the clips(such that the side to which the wires are soldered faces the pressure window) and tighten the screws which hold the clips to the snout just snug enough to hold the grid in place. It is important not to overtighten to avoid a leak in the o-ring seal. The second diagram shows the mechanics involved in holding the grid on the snout. The final figure is a link to a photo of the installed grid, taken at Pole.