This lists the physical dimensions of the NEWFIRM optical components and intercomponent spacings at fabrication temperature (293 K). These are derived from the cold optical design. These dimensions were used for all mechanical designn work on the optics mounts and the optical support structure.
The lens dimensions are as specified to the vendor. The Lyot stop diameters are specifications for the design. Recall that this is a toroidal aperture in a metal plate, hence the outer diameter (OD) and inner diameter (ID) dimensions. The OD is slightly undersized and the ID slightly oversized with respect to the optical design. This allows some tolerance for alignment of the instrument to the telescope.
The detector size includes a 4mm allowance for dead space between active areas of the arrays.
A side view of the optical layout in included below the table for component identification. Note that only one filter is shown.
Focus to 1st
Focus to 2nd
|Distance Z axis
to 1st Surface
|Distance Z axis
to 2nd Surface
between lens surfaces
|Lyot stop OD
Lyot stop ID
|Lyot stop arms||7.32j|
|Lens 8 seat||165.00||----||----||1273.4571a||----||282.56778b||----|
All dimensions noted are in millimeters.
aCenterline of lenses 7 and 8 and Detector
bFarthest lens seat from the Z axis
cDistance from lens 6 surface to fold mirror surface
dDistance from fold mirror surface to lens 7 first surface
eDistance from lens 8 second center vertex to detector plane
fDistance from lens 8 seat to detector plane
gDistance between lens 7 and lens 8 surfaces
hLyot stop aperture is a doughnut with central obstruction. Dimensions include deliberate under/oversizing of 0.127 mm for alignment tolerance.
jLyot spider arm thickness, allowing for optical blurring and ±1 deg rotational misalignment. The arms are at 45 deg to the cardinal points.
NEWFIRM with Fused Silica field lens. Total warm length 1368.69 mm, largest distortion 1.3%, largest skew ray angle on filter 13.52 deg.
Updated on September 5, 2023, 12:52 pm