Thermal compensation for optical apparatus
US6650412B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 2000 |
| Grant date | Nov 18, 2003 |
| Priority date | — |
| Expiry date | Feb 16, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/028
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Reliable and economical passive thermal compensation in both focus (parallel to the optical axis) and lateral position (perpendicular to the optical axis) is disclosed for optical apparatus, including spectrographs. In the preferred embodiment, to maintain the position of the lens along the optical axis, two or more polymer spacers are used between the lens mount and a floating flange to which the lens is attached. The polymer spacers have a thermal coefficient of expansion such that when the temperature increases the lens is moved toward the detector array by the spacers to compensate for the normal increase of the lens-detector spacing with temperature. Flexure mounts, which bend by a predetermined amount in a known direction when the temperature changes, are preferably used to connect the lens mount to the floating plate, thereby moving the lens in a direction lateral to the optical axis. In the case of a spectrograph, this lateral motion maintains the positional stability of given spectral lines on their respective detector pixel elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.