IFU for HET JCAM/MRS

Entries

Feb 23 2001 - Current Spider Head and Cable End

Here's the head that we either have to dissolve in acetone or cut off. We'd loose about 1+ inch if we cut.

IFU head
(approx 1 in),
angled view
Head height and width is 4.2mmx4.15mm.
side view
top view
The current total exposed fiber length (including about 1 inch of head) is 14.4 inches. If we cut off the head, we'd probably be down to 13 inches of exposed fiber (including the new head).

The teflon/shrink-wraped cable diameter is 1.02-1.035 inches, starting at 14.4 inches back from the head, and continuuing for 2.25 inches. 16.65 inches back from the head the cable increases slightly in diameter to 1.09-1.11 inches.

exposed cable at head (14.4 inches)
 close-up of teflon entry-point

Jun 24 2001 - Spider Redesign into HexPak

This is the "current" Spider design, implemented in the above bundle.

51 total fibers; 6 sky fibers; Head height x width = 4.2mm x 4.15mm.

A new HET/IFU design (HexPak)

The outer dimensions of the head shown here are identical to the above Spider head. However, we would like to increase one of the dimensions to place sky fibers at a good distance from the central array.

51 total fibers; 8 sky fibers
Head height x width: 4.2mmx4.15mm
[postscript]    [jpg]
 51 total fibers; 6 sky fibers
Head height x width: 4.2mmx4.15mm
[postscript]    [jpg]

Here are three options for integrating sky fibers into IFU head.

51 total fibers; 6 sky fibers
Head height x width: 4.2mmx7.45mm
[postscript]    [jpg]
 51 total fibers; 6 sky fibers
Head height x width: 4.2mmx6.35mm
[postscript]    [jpg]
 51 total fibers; 6 sky fibers
Head height x width: 4.2mmx5.8mm
[postscript]    [jpg]

Here's our 'final' design:.

51 total fibers; 7 sky fibers
Head height x width: 4.2mmx7.45mm --CHECK THIS
[postscript]    [jpg]

Nov 20 2001 - Revise -- Final ??? Design

At this time (as of Dave's departure for the Father Land) we conclude that making the above HexPak -- or any "standard" pure fiber pack with the 200:230:260 fiber is not possible because the fibers are not well enough behaved. (However note that our earlier results (see Test Array #2) showed a 10x11 array of 200:220:240 fiber. So either Dave has to "remember" his technique and find time to "remember" it, or we need a new way to proceed.

Here is an ugly option for a new way:

Purchase Connecticut Hypodermic custum-cut 0.75in length, thin-wall micro-tubes; make micro-tube array, and place one fiber per tube. I estimate CH's 26TW micro-tubes are the smallest we can use. This yields 457-467 micron OD and 292-330 micron ID. This will drastically increase the spacing (factor of 2), but will improve on FRD characteristics and polishing since we can use Norland. However, with space limitations in width dimension in long-slit probe in FIF from LE, this limits interesting geometry of array. Here is a default array:

51 total fibers; 7 sky fibers
Head height x width: 4.2mmx6.35mm -- CHECK THIS
[postscript]    [jpg]
Opinions ?
Other options?
Name for this brick ?