Wiring pattern detection method and apparatus
US5011960A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 1989 |
| Grant date | Apr 30, 1991 |
| Priority date | — |
| Expiry date | May 9, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/308
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of detection of a wiring pattern using triangulation to detect a height thereof, comprising the steps of scanning a light beam from a light source, illuminating the wiring pattern to be detected by the scanned light beam, focusing the light reflected from the wiring pattern or a substrate, applying the focused light beam to a beam-splitter, and converting a wiring pattern configuration to a corresponding electric signal. Further, by blurring the focused light entering the beam-splitter, an expansion of a measurable height domain of the wiring pattern is possible. Furthermore, by applying a correction factor in response to the height of the substrate, the detected output of the wiring pattern height for a curved substrate can be sliced with a more appropriate slice level. Further, the beam-splitter comprises a reflection portion, a half reflection and half transmission portion, and a transmission portion. The width of the half reflection and half transmission portion is such that an upper and lower threshold value of the height of the wiring pattern can be determined, and thus the allowable limits of the wiring pattern height can be more accurately detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.