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Summary
| Description |
English: A flatness test of a piece of 9--14λ plate glass, taken from a picture frame. The upper photo shows the plate glass (8x10 inches)in contact with a 4--6λ float-glass optical window (2 inches square) @ 450 nm. The lower left photo shows the plate glass being tested with a λ/10 optical flat (2 inch diameter), while the lower right photo shows two pieces of the same plate glass, cut into 1 inch squares. The optical flat shows a flatness of 9--14λ for the piece of plate glass (at 520 nm), while the test with the float glass surface measures only 5--9λ. When the two pieces of plate glass are put together (@ 450 nm), the test shows near perfect flatness, warping a little only because of the minimal thickness of the material (1/16 inch for the plate glass, 1/8 inch for the float glass and 1/2 inch for the optical flat). |
| Date | 4/6/2017 |
| Source | Own work |
| Author | Zaereth |
Licensing
I, the copyright holder of this work, hereby publish it under the following license:
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
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- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
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File history
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 21:05, 11 April 2017 | | 1,805 × 1,769 (3.3 MB) | Zaereth | Added other test surfaces to the plate glass for comparison |
| 07:11, 7 April 2017 |  | 1,805 × 1,133 (2.42 MB) | Zaereth | User created page with UploadWizard |
File usage
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