December, 2000 WFC3 Critical Design Review 1

WFC3 Critical Design Review

CONFIGURATION OVERVIEW

Jim Sneary

December, 2000 WFC3 Critical Design Review 2"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Description Outline

• Location within HST• System / Subsystems Layout• Post SRR Changes

December, 2000 WFC3 Critical Design Review 3"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Continuing The HST LegacyUltimate In-Service Replacement

WFC3 will replace WFPC2in the Aft Shroud -V3 axis

December, 2000 WFC3 Critical Design Review 4"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

WFC3 Is A Hubble Space Telescope Radial Instrument

+V2NCS

Radiator

Bay 2 Bay 3

Bay 4

Bay 1

WFC3

STISCOS

ACS NICMOS

+V3

+V2

ESMNCC

FGS 2

FGS

3

FGS

1

WFC3

WFC3

HST

WFC3 utilizes theenclosure andradiator of theretrieved WF/PC 1

WFC3 will maintainthe same mechanicaland electrical interfacesas WFPC2

December, 2000 WFC3 Critical Design Review 5"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Numerous WF/PC 1 ComponentsAre Being Reused On WFC3

Main (Detector)Radiator

Mechanism Cover

Enclosure

Radiator TrussAssembly

B-Latch

A-Latch

GSE Pick-OffMirror Cover

Guiderails C-Latch(hidden)

WF/PC1 H/Wreuse items

GSE RotatingDolly

December, 2000 WFC3 Critical Design Review 6"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

WFC3 Has SignificantSubsystem Heritage

Enclosure

Main (Detector)Radiator

Radiator TrussAssembly

WF/PC I H/W reuse

B-Latch

A-Latch

Blind Mate Connector

MechanismCover

LVPSMEB #2

DEB (under MEB)

MEB #1

CEB

Pick-OffMirror & Arm

Detector Heat Pipes

HST Heritage

ElectronicsRadiator

Optical Bench

New H/W

December, 2000 WFC3 Critical Design Review 7"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Electrical SubsystemSimplified Block Diagram

HST

Power

Command/

Housekeeping RIU

LVPS

Control

Section

Support

Electronics

Section

UVIS CEB

IR DEB

Housekeeping Data (thermistors) Calibration

Lamp ControllerMechanisms

(6)

Science Data

Formatter

ThermalControllers (4)& RadiatorTEC

1. Only one side shown2. Cross-strapping not shown3. Not shown: - RIU Expander Unit - SOFA Relay Box - Power Distribution Box

UVIS CCD TEC

IRFPA TEC

Filter Box

Filter Box

Cal Lamps

MEB

= redundant boxes

= redundant circuitryon the PWAs

December, 2000 WFC3 Critical Design Review 8"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

CCDElectronicsBox (CEB)

MainElectronicsBox 1(MEB1)

Low VoltagePower Supply(LVPS) 1 & 2

SOFAElectronics

Bay 1

Bay 5

Bay 2

MainElectronicsBox 2 (MEB2)

Detector (IR)Electronics Box(DEB)

Heater PowerDistribution Box(HPDB)

ExternalRadiator

Calibration LampsController (CLC)

Blind MateConnector

Enclosure

Remote InterfaceUnit (RIU) 1 & 2 ;Extender Unit(EU) On back ofrear enclosurebulkhead and notshown here

Electronics Locations On WFC3

December, 2000 WFC3 Critical Design Review 9"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Wide Field Optical Diagram

UVIS Channel • FOV 160 X 160 arc sec• F/31• OTA + WFC3 focal length = 78,000 mm• 4k X 4k CCD, 15 mm pixels• 200 - 1000 nm

IR Channel

• FOV 123 X 139 arc sec• F/11• OTA + WFC3 focal length = 29,000 mm• 1k X 1k HgCdTe array, 18 mm pixels• 850 - 1700 nm

December, 2000 WFC3 Critical Design Review 10"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Highlights Of Post-SRR Changes

• Reflective IR optical configuration changed to a refractivesystem– Incorporation of a refractive corrector plate (RCP) and an optimized ‘co-located’ cold stop– Benefit is overall instrument throughput improvement from 61 to

85 %

• Both detector focal planes (UVIS and IR) are mounted at anangle to optic axis to account for off-axis opticalprescriptions

• Numerous packaging iterations for locations of mechanismsand electronics boxes.

• Down-selected to Marconi CCD for ;– Noise performance and considerations for coating / QE stability and

CTE

December, 2000 WFC3 Critical Design Review 11"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

UVIS Channel Detector

• Format: 2 x 2Kx4K CCDs• Pixel size: 15 mm• Field of View: 160x160 arcsec• Bandpass: 200 to 1000 nm• Read Noise: < 4 e- rms• QE > 60% for 300 to 700 nm• Charge Transfer Efficiency: > 0.99999 (start of life)• Dark current: < 15 e-/pix/hr

Two per assembly

2k x 4k CCD

BasePlate

UpperRadiationShield

FocalPlane

CEBElectronics

Enclosure

Hardware from ACSWide Field Camera

December, 2000 WFC3 Critical Design Review 12"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Cover, thermal shieldand baseplate

Mounted FPAwith discretelead wires

6-stage TEC& ceramiccup withCu straps

5.5” dia.

IR Demo Hardware- Designed, Fabricated And Tested -

•Format: 1Kx1K HgCdTe/Silicon mux•Pixel size: 18 um •Field of View: 130x130 arcsec•Bandpass: 850 to 1700 nm

Filter WheelMechanism

ColdEnclosure

IR Detector Assy

Filters

One1 K x 1 K FPAper unit

December, 2000 WFC3 Critical Design Review 13"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

Optical Assembly WithTop Panel Removed

SOFA (UVIS Filters)

WF/PC I H/W reuse

UVIS Detector

UVIS Shutter

Calibration Subsystem

IR Fold Mirror

IRM2 & CorrectorMechanism

Athermalized Strut System

UVM1 & CorrectorMechanism

IR Filter Wheel

Pickoff Mirror

HST Heritage

Channel SelectMechanism

IR Cold EnclosureRCP

IR Detector

Optical Bench

New H/W

December, 2000 WFC3 Critical Design Review 14"Data contained herein is exempt from ITAR regulations under CFR 125.4(13) -- data approved for public disclosure."

WFC3 Thermal Configuration

UVIS FlexCCHPs (2)

MEB CCHPs(2) Internal(2) External

IR Cold Enclosure Flex CCHPs (2)

IR Detector Flex CCHPs (2)

Optical Bench Cold Platewith Integral CCHP (1)

External Radiator with ExternalSpreader CCHPs (6) and

Header CCHPs (2)

Optical Bench Cold PlateControl VCHP (1)

MEB CCHPs(2) Internal(2) External