Non-contact electro-optical displacement follower
US4682221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1984 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | Oct 31, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This invention relates to a non-contact electro-optical displacement follower which captures the image of a target or device under test optically, converts the said image into an electron image by optical-electrical conversion, and measures displacement. It forms a variable voltage which moves the electron image on the displayer to the desired location and can be applied to each deflection coil (8, 9) by arranging a variable voltage generator (18h, 18v) attached to each deflection coil so that the set-up and adjustment of the equipment and measurement preparations can be performed easily. Moreover, this equipment possesses a displayer (A1, A2, A3, A4) to indicate which position (up, down, right or left) the electron image moved due to the variable voltage, in spite of the fact that the electron image may be damaged temporarily if adjustment is excessive. Additionally, a non-contact electro-optical displacement follower of this invention can be equipped with a Light Servo circuit (27, 28) whose frequency response will eliminate effectively any optical noise changing in high speed. It also comes equipped with operation instructions to advise operators directions for each mode the equ…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.