Tab_02_-_Specifications.pdf

Specifications for Germanium Windows for IR Thermography

NASA Langley Research Center requires four, Germanium windows for flow physics research.

These windows will be used with Infrared cameras in wind tunnel tests to detect boundary layer transition using Infrared Thermography.

Each window shall have the following characteristics:

1. The window shall be Germanium. A material data sheet shall be provided.

2. The diameter of the window shall be 139.7 +0/-0.20 mm.

3. The thickness of the window shall be 14 +/-0.20 mm.

4. The transmission through the window shall be greater than 94% from 3-12 μm at 0.0 degrees viewing angle. The measured transmission curve shall be provided.

5. Both sides of the window shall be coated with an anti-reflective coating.

6. The anti-reflective coating shall meet MIL-C-48497A. A certificate of conformance shall be provided.

7. The flatness of the window shall be less than 4 waves per 2.0 inches.

8. The parallelism of the window shall be less than 3.0 arc minutes.

9. The cosmetic finish of the window shall have a scratch and dig classification of 60/40 or better.

10. The window shall have a 45 degree bevel according to the attached drawing and meet any additional specifications listed thereon.

11. 2 windows shall be delivered by October 14, 2016. Remainder of order to be delivered no later than November 14, 2016.

**The vendor shall provide technical literature in order for the Government to evaluate the quotes submitted based on technical merit

8 7 6 5 4 3 1

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A

B

C

DD

C

B

A

CAGE DWG. NO. SH REV.

NATIONAL AERONAUTICS & SPACE ADMINISTRATION

LANGLEY RESEARCH CENTER

HAMPTON, VA 23681-0001

TITLE

DWG.

NO.

CAGE CODESIZE REV.

SHEETSCALE ACT. WT.CALC. WT.

PARTS LIST

DRAWN

CHECKED

DESIGNER

LEAD ENGR.

BRANCH

SPECIAL MARKING SYMSIMILAR TO

FINISH

TREATMENT

APPROVALS DATE

CONTRACT NO.

NOTES:

5.50

.55 .27

45.0°

4.94 REF

1 OF 11.000

-127353325305D

14' X 22' INFRARED WINDOW

TUNNEL MODIFICATIONS

GERMANIUM GLASS

ITEM

NO.

MATERIAL

SPECIFICATION

NOMENCLATURE

OR DESCRIPTION

PART OR

IDENTIFYING NO.CAGE CODE

QTY REQD

-1-3

1GEGERMANIUM GLASS-14

NOTED

NOTED

APPLICATIONQTY REQD

PER ASSY

PART

DASH

NO.

USED ONNEXT ASSYFINALNEXT

1273528-11273529-141-1

REVISIONS

APPROVEDDATEDESCRIPTIONREVZONE

25305 1273533 1 -

05/19/16V. LE BOFFE

05/19/2016 V. LE BOFFE

UNLESS OTHERWISE SPECIFIED

DIMENSIONS ARE IN INCHES

TOLERANCES

DECIMALS ANGULAR

.XX 0.02 .X 0.1

.XXX 0.005

DO NOT SCALE DRAWING

1. ALL SPECIFICATIONS APPLY OVER THE CLEAR APERTURE ONLY. CRACKS ARE NOT ACCEPTABLE ANYWHERE ON OR

IN THE WINDOW.

2. EDGE CHIPS SHALL CONFORM TO MIL-PRF-13830. PARAGRAPH 3.7.9.2.

3. EDGES WILL BE FINE GROUND. BEVELS MAY BE POLISHED TO ACHIEVE WAVEFRONT REQUIREMENTS.

4. SURFACE QUALITY OF "S1" AND "S2" SHALL MEET THE 60/40 SCRATCH/DIG SPECIFICATION IN MIL-PRF-13830 WHERE

THE SCRATCH NUMBER DENOTES THE SCRATCH WIDTH IN MICRONS.

5. WAVEFRONT QUALITY:

1. THE TRANSMITTED WAVEFRONT ERROR SHALL BE MEASURED IN COLLIMATED LIGHT AT 632.8 NM WITH LIGHT TRANSMITTED OVER THE FULL CLEAR APERTURES DESIGNATED ON SIDES "S1" AND "S2". (LACKING A FULL

APERTURE INTERFEROMETER THE INTERFROGRAMS CAN BE STITCHED TOGETHER.)

2. THE TRANSMITTED WAVEFRONT ERROR AT 632.8 NM SHALL BE LESS THAN 0.5 WAVES RMS FOR THE FULL CLEAR

APERTURE.

6. SURFACES "S1" AND "S2" SHALL HAVE A HARD DIELECTRIC ANTIREFLECTIVE COATING APPLIED OVER THE FULL APERTURE LIMITED BY FIXTURING. AR COATING SHALL MEET THE FOLLOWING TRANSMISSION REQUIREMENTS

OVER THE CLEAR APERTURE:

1. AVERAGE TRANSMITTANCE >94% FROM 2.5 - 13.5 MICRONS AT ANY ANGLE OF INCIDENCE UP TO 24.2 .

7. COATINGS SHALL MEET THE FOLLOWING REQUIREMENTS OF MIL-C-48497A INCLUDING THE FOLLOWING

PARAGRAPHS:

1. 4.5.3.1 ADHESION

2. 4.5.3.2 HUMIDITY

3. 4.5.5.3 MODERATE ABRASION

4. 4.5.4.1 TEMPERATURE

5. 4.5.5.2 SALT SOLUBILITY

6. 4.5.5.3 WATER SOLUBILITY

8. WEDGE BETWEEN SURFACES "S1" AND "S2" SHALL NOT EXCEED 0.008°.

9. IDENTIFY PER MIL-STD-130 (BAG AND TAG) WITH PART NUMBER "1273533-1".

-1 GERMANIUM GLASS (4 REQ'D.)

ISO VIEW

SCALE 1.000

R. MIN.

R. MIN.

R. MIN. S1

S2

SCALE 1.000