1/30 March 2007SECCHI Consortium Meeting - Paris HI straylight performances Design, pre-flight test data and in flight results J.P. Halain – Centre Spatial.

March 2007 SECCHI Consortium Meeting - Paris 1/30

HI straylight performancesDesign, pre-flight test data and in flight results

J.P. Halain – Centre Spatial de Liège

with J.M. Defise, E. Mazy, A Mazzoli - CSL (Belgium)D Moses, J Newmark, C Korendyke, D Socker - NRL (US)C. Eyles, R. Harrison, C Davis - UB, RAL (UK)


Summary

• HI Instrument concept » Main challenges» HI Straylight requirements» Instrument design (diffractive and reflective baffles)

• HI preliminary in-flight straylight results» Off-pointing results» Straylight pattern analysis» In and out-FOV results

•HI pre-flight performance measurements» Spot and photometry results» Sun-limb, off-pointing and out-FOV straylight results


HI Instrument Concept

Main challenges:• Faint detection capability (10-15 B0) high stray-light rejection requirements• Large FOV specific optics

Solar light

Forward BaffleInternal Baffle

HI 1HI 2


Stray-light requirements

Instrument background straylight requirements:

< 3x10-13 B/B0 for HI-1

< 10-14 B/B0 for HI-2

HI Straylight Requirements

Major stray-light contributors

• Direct solar light (B0 !)

• Bright sources in and out FOV (Earth)

• Payload elements near the UFOV

Background composed of F-corona,

planets, stars, Earth and moon

HI-1

HI-2


HI Design – Forward Baffle

1.E-12

1.E-11

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

1.E-02

1.E-01

1.E+00

0 0.02 0.04 0.06 0.08 0.1

X [mm]

Rej

ecti

on le

vel

vane #1

vane #2

vane #3

vane #4

vane #5

HI-1 optics HI-2 optics

1.E-12

1.E-11

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

-6-5-4-3-2-10

Angular offset [arcdeg]

Rej

ecti

on [

B/B

0]

Theoretical values

Ambiant HI-EQM

Vacuum HI- EQM

Front baffle concept with the location of the HI-1 & 2 optical systems

Intensity profiles measured with the 5-knive edge mock upin air and in vacuum, measured @CSL

forward baffleHI-1

HI-2

X

HI cascading knives-edges forward baffle computed efficiency


HI Design – Internal Baffle

80

60

40

20

0

-20

-40

-60

-8080 70 60 50 40 30 20 10 0 -10 -20 -30 -40 -50 -60 -70 -80

Elevation X

[arcdeg]

Elevation Y [arcdeg]

-5.00--4.00

-6.00--5.00

-7.00--6.00

-8.00--7.00

-9.00--8.00

-10.00--9.00

Sun Side

Computed performance at HI-2 entrance (log)

Straylight level in HI-1 and HI-2 (nominal orbit)

Internal baffle ray-tracing model


F/3 collimator

Primary Optical Characterization Collimator

To View Stray Light CollimatorRotate Instrument on the GSEPedestal by 6o relative toPrimary Collimator Alignment

N ew port R V 350

C O G

( 0 ,0 )

C O G

Interface plane

A

parabo

la focus

Interface plane

STERE O

A

B

C

D

E

F

F

E

D

C

B

A

détecteur (photo-diode)

Instrum ent H i

position des panneaux froids

tente C orot

collim ateur H ipparcos

cuve Focal 3

HI pre-flight performance measurement

HI-A and HI-B flight models optical performances and end-to-end straylight verification NB: instrument axis at 3.65-arcdeg

Black enclosure

HI instrument

Light source collimator


Pre-flight: HI-A In-field results

0

10

20

30

40

50

60

70

80

90

-90 -80 -70 -60 -50 -40 -30 -20 -10 0

Pitch [arcdeg]

HE

W [

µm

]

HI1/HI2Overlap

EarthOcculter

HI-2 FOV

HI-1 FOV

-73.5°

5.54°

HI-A spot measurements : (1 px = 13.5µm) 38.8µm < HI-1 RMS spot diameter < 54.3µm 31.5µm < HI-2 RMS spot diameter < 78.1µm

NB: - photometry results of HI-A pre-flight calibration are limited by smearing- straylight results are limited by chamber background

Hal

f E

nerg

y Sp

ot W

idth

[µ

m]

Design values:

45µm < HI-1 < 67µm

105µm < HI-2 < 145µm


Pre-flight: HI-B In-field results

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

160.0

180.0

-90 -80 -70 -60 -50 -40 -30 -20 -10 0

Pitch [arcdeg]

HE

W [

µm

]

EarthOcculter

HI1/HI2Overlap

-73.5°

5.54°HI-2 FOV HI-1 FOV

HI-B Photometry• HI-1B detector conversion: 30345 photon/DN@670nm• HI-2B detector conversion: 52626 photon/DN@670nm

HI-B spot measurements : (1 px = 13.5µm) 37.9µm < HI-1 RMS spot diameter < 49.8µm 68.6µm < HI-2 RMS spot diameter < 164.8µm (border of FOV)

Hal

f E

nerg

y Sp

ot W

idth

[µ

m]

Design values:

45µm < HI-1 < 67µm

105µm < HI-2 < 145µm


Pre-flight: HI-1B straylight (sun limb)

Curtain Edge

130DN = 3∙10-13 B/B0 (at requirement level)

127DN = 7.5 10-14 B/B0

Super Black Panel

Laser Beam(B0)

Straylight verification with reference black panels and collimated laser beam @670nm

133DN = 5∙10-13 B/B0

Underscan columns = 126 DNB0 = 1.33 1013 DN =4 1017 ph720s integration time

HI-1B image taken @CSL


Pre-flight: HI-1B straylight (off-pointing)

3∙10-13 B/B05∙10-13 B/B0

7.5∙10-13 B/B0

Ring appears4∙10-11 B/B0

1.2∙10-12 B/B0

1.8∙10-10 B/B0

4∙10-12 B/B0

10-9 B/B0

2∙10-9 B/B0

5∙10-7 B/B0

8∙10-12 B/B0 1.2∙10-11 B/B0

0 0.17 0.33

0.5 0.66 1.0


Ring pattern dominate diffractive pattern in HI-1 straylight

Diffractive pattern

Ring pattern

Pre-flight: HI-1B straylight (1-arcdeg)

Detail of HI-1B image taken @CSL , with collimated beam at 1.5-arcdeg from sun-limb direction


3.6∙10-11 B/B0

Pre-flight: HI-1B straylight (diffraction)

Detail of HI-1B image taken @CSL , with collimated beam at 1.5-arcdeg from sun-limb direction

5∙10-7 B/B0


Various offset angles at border of HI-1 FOV (3.65 – 23.65-arcdeg)Ring pattern visible + other ghosts

4.1∙10-8 B/B0 4.6∙10-9 B/B0

1.5∙10-7 B/B0

2.4∙10-8 B/B0

Pre-flight: HI-1B straylight (out FOV)

5∙10-8 B/B0 4.6∙10-8 B/B0 5.5∙10-8 B/B0

4.2∙10-8 B/B03∙10-8 B/B0

4∙10-8 B/B01.1∙10-8 B/B0

In FOV

2.5 3.5 4 4.5 5

24 25 26 27 30


1.2∙ 10-13 B/B0

Super Black Panel

Super Black Panel

At Requirement

level:1.2∙ 10-14 B/B0

1.5∙ 10-15 B/B0

Pre-flight: HI-2B straylight (sun limb)

Laser Beam(B0)

Black enclosure

HI-2B image taken @CSL

Earth occulter


Laser Beam(B0)

Pre-flight: HI-1&2B (sun limb)

Combination of HI-1B and HI-2B images taken @CSL


Pre-flight: HI-2B straylight (out FOV)

1.2∙10-10 B/B0

2.7∙10-8 B/B0

4.3∙10-8 B/B0

2.6∙10-8 B/B0

1.7∙10-8 B/B0

4.3∙10-8 B/B0

4.5∙10-10 B/B06.4∙10-10 B/B0

Various offset angles at border of HI-2 FOV (18.36 – 88.36-arcdeg)Internal baffle illuminated + ghosts

10 15 90

100 120 140


Approximate Location of

Sun

Ecliptic Plane

First Flight Image – HI-1A

13-Dec-2006

F-CoronaSymmetric with Ecliptic


Earth Occulter

Inner BaffleIlluminated by Earthshine

F-CoronaSymmetric with Ecliptic

Ecliptic Plane

Approximate Location of Sun

First Flight Image – HI-2A

13-Dec-2006


In-flight: HI-1A & B straylight (off pointing)Off-pointing 10-Jan-07 and 13-Jan-07

HI-1A

HI-1B

1.2∙10-11 B/B0

2∙10-12 B/B04.8∙10-10 B/B0

> 5∙10-10 B/B01.1∙10-11 B/B0

1.2∙10-12 B/B0

0 1.0 1.5

0 1.0 1.5


0 0.24 0.5

0.75 1.0 1.5

Off-pointing 30-Jan-07

In-flight: HI-1A straylight (off pointing)

5.3∙10-13 B/B0 8.2∙10-13 B/B09.8∙10-12 B/B0

7.9∙10-11 B/B01∙10-12 B/B0 1.9∙10-12 B/B0

1.1∙10-11 B/B0 5∙10-10 B/B06∙10-12 B/B0

5∙10-12 B/B04∙10-12 B/B03.5∙10-12 B/B0


In-flight: HI-1 straylight comparison

1.E-13

1.E-12

1.E-11

1.E-10

1.E-09

1.E-08

1.E-07

1.E-06

0 0.2 0.4 0.6 0.8 1 1.2

Offset angle [arcdeg]

Str

aylig

ht le

vel [

B/B

0]

HI-1B (12-11-2006) @ CSL - Background

HI-1B (12-11-2006) @ CSL - Ring

HI-1A (30-01-2007) in flight - background

HI-1A (30-01-2007) in flight - Ring


Diffractive pattern

Ring pattern

In-flight: HI-1A straylight (1.5-arcdeg)

Similar combination of diffractive and ring pattern as measured @CSL(instrument pointing during tests 13.65-arcdeg vs. in flight pointing 13.98-arcdeg)

7.9∙10-11 B/B0

> 5∙10-10 B/B0

2∙10-10 B/B0

1.5


HI-1 straylight: ring pattern analysis

Ray-tracing model of HI-1 lens barrel shows that the 2 last retainers generate the ring pattern

FOV border (3.65-arcdeg)

FOV border - 3 arcdeg(0.65-arcdeg)


HI-1 straylight: ring pattern analysis (2)

FOV border - 10 arcdeg

FOV border - 15 arcdeg FOV border - 20 arcdeg

FOV border - 7 arcdeg


In-flight: HI-1 straylight (out-FOV)

HI-1 B (1-Feb-07) HI-1 B (3-Feb-07)

Earth arriving close to the HI-1B FOV on beg. February 07 (before entering in FOV) confirms the preliminary analysis of ring pattern (no diffractive pattern in the ring)

30 26


In-flight: HI-1 straylight in-FOVSimilar ring straylight pattern with a bright star (in FOV), probably due to other similar parts of the lens barrel (ghost). TBC.

1.3∙10-12 B/B0

> 2∙10-9 B/B0


In-flight: HI-2 straylight (out-FOV)

The 5 oval edges are in the FOV and imaged.Preliminary explanation is Earth close behind instrument and illuminate internal baffles from rear

HI-2 A (13-Dec-06) HI-2 B (15-Jan-07)

88,425


In-flight: HI-2 straylight (in and out FOV)Earth crossed HI-2B FOV beg. of February

Earth behind instrument is not the only straylight sources in HI-2 (SWAVES boom ?)

In FOV

90140 120 100

80 50 20 10


Conclusions

Preliminary straylight comparisons

In-flight straylight / ghosts are qualitatively similar to the pre-flight measurements

Comparable sun limb straylight level in HI-1, but lower in-flight off-pointing values

Ring pattern in HI-1 preliminary analysis result

Work plan for CSL

Continue HI-1 and HI-2 in-field and at border of FOV analysis

Straylight quantitative results to be continued and refine (additional off-pointing)

Earth and SWAVES boom effect in HI-2 to be confirmed when Earth will be further

Comparison of HI-2 straylight with Earth-S/C-Sun angle

Ghosts and straylight to be re-evaluated when in nominal orbit with Earth far enough

In-flight calibration and F-Corona removal for straylight analysis results improvement

Instrument other performances analysis

• Compare PSF to have a model of PSF for de-convolution

• Characterize PSF as function of position in CCD

• Characterize distortion for correction


Back-up slides


Pre-flight: HI-1A straylight (0-arcdeg)

Beam(B0)

7.1x10-11 B/B0

2x10-9 - 5x10-10 B/B0

2.1x10-10 B/B0


2x10-10 B/B0

4x10-11 - 2x10-12 B/B0

Pre-flight: HI-2A straylight (0-arcdeg)

Beam(B0)

1/30 March 2007SECCHI Consortium Meeting - Paris HI straylight performances Design, pre-flight test data and in flight results J.P. Halain – Centre Spatial.

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