# Presentation: 105174

## MAXIM Periscope Module

**Optics**
**Dennis Charles Evans**
**25 April 2003**

## Mirror Parameters

- TBD

- Active area is  30 cm long by either 2,10 or 30 cm wide-  so **THREE different types of mirror modules for a trade study**
- Surface figure requirement: /200 rms (at 633nm)
- Mirror mass must be minimized
- Surface Figure and Micro-roughness indicate a stable glass substrate such as    ULE, ultra low expansion glass
- For Baseline, width was set at 20 cm so metallic silicon could be used.

- 2,10, and 30 cm
- TRADE STUDY

- Mirror surface

## Lightweight ULE Mirror

**Lightweight ULE Mirror**

## Kodak Lightweight Cryostable Mirror

**Kodak Lightweight Cryostable Mirror**

## Kodak Lightweight Cryostable Mirror

**Kodak Lightweight Cryostable Mirror**

## MAXIM Pathfinder IMDC Study May 2002

- ATAN 0.5/20000 = 5.156620 arc sec

## Collector Area

**Collecting Area**
**	****	****Each Unit is a collection of 2 sets of 4 mirrors on one common bench**
**	****	****30 × SIN 1 = 0.52357219311850536 cm projected width**
**	****	****0.52357219311850536 ×20 = 10.471443862370108 cm****2**
**Each 20 cm wide set has 10.47 cm****2**** collecting area**
**Goal is to have 1000 cm****2**** area**
**Hub= 6 units (12 sets)****	****[  48 mirrors]**
**Satellite= 25 (4 sets)****	****[400 mirrors]**
**	****	****((25 × 4)+12) × 10.46    = 1172.64**
**	****	****((25 × 4)+12) ×  8.9286 = 1000.0031999999998**
**8.9286 ÷ 0.52357219311850536 = 17.053235670938506 Clear Width**
**28 × SIN 1 = 0.48866738024393832**
**0.48866738024393832×18.272 = 8.92893037181724**
**Mirrors Physical:   30 cm long and 20        cm wide**
** ****Clear Footprint:   28 cm long and 18.272 cm wide**

## Collector Area & Free Flier Tradeoff

| Apertures | Baseline
30 x 20 cm blanks
8.929 cm2 | Baseline x 1.5
30 x 29 cm blanks
13.394 cm2 |
| --- | --- | --- |
| Hub  | [6x2=12]
107.1 cm2 | [4 x 2=8]
160.7 cm2 |
| Free Fliers | [25 x 4=100]
892.9 cm2 | [17 x 4=68]
910.8 cm2 |
| Total Area | 1000 cm2 | 1071.5 cm2 |
| Mass Ratio | 1x 31=31 | 1.5 x 21 = 31.5  |
| Cost | Baseline | 17/25=0.68 for FF S/C!  |

## Aperture Locations at 20,000 and 500 km Focal LengthZEMAX Configurations

**   ****Location_20000                Location_500**
**   ****1   0  10                     1   0  0.25**
**   ****2  60  11.8                   2  60  0.295**
**   ****3 120  13.9                   3 120  0.3475**
**   ****4 180  16.4                   4 180  0.41**
**   ****5 240  19.4                   5 240  0.485**
**   ****6 300  22.9                   6 300  0.5725**
**   ****7   0  27                     7   0  0.675**
**   ****8  60  31.9                   8  60  0.7975**
**   ****9 120  37.6                   9 120  0.94**
**  ****10 180  44.4                  10 180  1.11**
**  ****11 240  52.3                  11 240  1.3075**
**  ****12 300  61.8                  12 300  1.545**
**  ****13   0  72.9                  13   0  1.8225**
**  ****14  60  86                    14  60  2.15**
**  ****15 120 101.5                  15 120  2.5375**
**  ****16 180 120                    16 180  3**
**  ****17 240 141.3                  17 240  3.5325**
**  ****18 300 166.7                  18 300  4.1675**
**  ****19   0 196.7                  19   0  4.9175**
**  ****20  60 232.1                  20  60  5.8025**
**  ****21 120 274.9                  21 120  6.8725**
**  ****22 180 323.2                  22 180  8.08**
**  ****23 240 381.4                  23 240  9.535**
**  ****24 300 450.1                  24 300 11.2525**
**  ****25   0 531.1                  25   0 13.2775**
**  ****26   0   0                    26   0  0**

## Aperture Locations

## Aperture Locations (central area)

## Optical Layout

- F

- R

- (F**2**+R**2**)^**0.5**

**OPD**

- R

**OPD/R = R/**(F**2**+R**2**)^**0.5****                  OPD=R****2****/**(F**2**+R**2**)^**0.5**

## Maxim “Quadriscope” Layout

## Sample Mirror Arrangement (10example)

**Using RTL to calculate central ray path**
**Delay Line Shift of 1 micron = 698 A Path Difference**

## Total Optical Path Differences

**Total Optical Path Difference (meters)**
**R=13.2775 ; F=500000 ; OPD=(R*2)÷((R*2)+(F*2))*0.5 ; OPD**
**0.00035258401237568448  (352584 nm)**
**R=.25 ; F=500000 ; OPD=(R*2)÷((R*2)+(F*2))*0.5 ; OPD**
**1.2499999999998436E ̄7   (125 nm)**
**Delay Line Sensitivity**
**352584 ÷ 69.8 = 5051.34670487106 units of 0.1 micron  **
**= 505 microns  = 0.000505 meters**

## Airy Diffraction “Rings” for 500 km

**OPD=1250A 500km**

**OPD=31.25A 20000km**

| Focal Distance = 500 000 000 mm |  |  |
| --- | --- | --- |
| “Diameter”
mm | Airy Radius
microns | Airy Radius
arc-sec |
| 25000  | 24.4  | 0.000 010 |
| 200 | 3.050 | 0.000 413 |
| 5 | 122.000 | 0.050 327 |

## Interference FringesPathlength Differences

- D

- 1 wavelength = 1 nm (10 Angstroms)

- A

- D=0.0000005 mm/TAN 5.156620/3600. = 0.020000 mm
- or 50 lines/mm

**0.5 nm**

## All 25 configurations geometrically aligned

## Configuration 1

## Configuration 1 4

## Configuration 1 4 7

**Configuration 1 4 7**

## Configuration 1 4 7 10

## Configuration 1 4 7 10 13 

## Configuration 1 4 7 10 13 16 

## Configuration 1 4 7 10 13 16 19

**Configuration 1 4 7 10 13 16 19**

## Configuration 1 4 7 10 13 16 19 22

## Configuration 1 4 7 10 13 16 19 22 25

## Configuration 1 2 4 7 10 13 16 19 22 25

## Configuration 1 2 3 4 7 10 13 16 19 22 25

## Configuration 1 2 3 4 5 7 10 13 16 19 22 25

**Configuration 1 2 3 4 5 7 10 13 16 19 22 25**

## Configuration 1 2 3 4 5 6 7 10 13 16 19 22 25

## Configuration 1 2 3 4 5 6 7 810 13 16 19 22 25

## Configuration 1 2 3 4 5 6 7 8 910 13 16 19 22 25

## Configuration 1 2 3 4 5 6 7 8 910 1113 16 19 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 16 19 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 16 19 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 19 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 19 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 25

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

**Configuration 1 2 3 4 5 6 7 8 9 10 11 12 ****13 14 15 16 17 18 19 20 21 22 23 24 25**

## Polychromatic Wavelengths

**For an 0.8A bandwidth and a center wavelength of 10A, the coherence length (resonance length) is approximately 125 A.**

## Configuration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

**Configuration 1 2 3 4 5 6 7 8 9 10 11 12 ****13 14 15 16 17 18 19 20 21 22 23 24 25**

## Y Cross section, All 25 Apertures, not phased

## Y Cross section, All 25 Apertures, not phased

## X Cross section, All 25 Apertures, not phased

**X Cross section, All 25 Apertures, not phased**

## Polychromatic Phasing, 22 & 25

## Polychromatic Phasing, 22 & 25

**Polychromatic Phasing, 22 & 25**

## Multi-configuration Variables

- 1:

- 1: Quadriscope Free Flier Azimuth (0=North)
- 2: Quadriscope Free Flier Radius distance
- 3: Inversion for Southern Quadriscopes
- 4: Mirror 4 X-Tilt
- 5: Mirror 4 Y-Tilt (Roll along length)
- 6: Mirror 1 Glass (use ‘blank’ as shutter)
- 7: Delay Line Shift (0.0000001m = 69.8 A OPD)

## Next Steps

**Fringe Phasing**
- monochromatic
- polychromatic (12 wavelengths in ZEMAX)
**Problem:**  It looks like ZEMAX is using paraxial parameters to compute optical paths for each calculation and not adjusting for real optical path.
- Delay line shifts of 0.0005 meters did not produce any effect in the fringe patterns.
- Shifts of 10 mm blocked the path and no image (no pupil) was produced.
- A Non-Sequential model may resolve this????
**Extend Source Image**
- “F”
- Star Image

## Next Steps – “F” Source

- F

- F

- F

- F

- F

- F

- F

- F

- F

- F

- F

- F

- R, Theta

- X Y
- or multiple Z rolls

- Next

## Back-up Slides

## MAXIM Periscope

**Improved Mirror Grouping**

- Group and package Primary and Secondary Mirrors as “Periscope” Pairs

## AutoCAD Layout Drawing

## 1 @ 25 meters, Separation = 446.8529mm

## Interference Fringes

- D

- 1 wavelength = 0.1 mm

- 1

- D=0.050/TAN 1 = 2.86 mm.     20mm/2.86mm=6.99

**0.050mm**

## Nonsequential ModelTwo Periscopes, 180, 100 

## Upper Periscope

## Geometric Ray Trace

## 100 microns wavelength

## Solid Model  100 micron wavelength

## 50 micron wavelength

## Solid Model  50 micron wavelength

## 12.5 micron wavelength

## 12.5 microns, 1/8 size

## 1.5625 microns, 1/8 size

## Sequential

## Periscope MirrorsFour configurations

## Sequential, 100, 

## NonsequentialTwo (180) Configurations

## NonsequentialAll Four Configurations

## Interpretation of Models

**Nonsequential Model**
- ZEMAX is calculating pathlength and phase correctly.
- The model is approximately a dual slit
- ZEMAX does not seem to be calculating intensity roll-off at all
**Sequential Model**
- The results from the sequential model, All Configurations, appears to be exactly the same as the Nonsequential model.