Lamp quality judgement apparatus and judgement method therefor
US4759630A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1986 |
| Grant date | Jul 26, 1988 |
| Priority date | — |
| Expiry date | Jul 31, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/433
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention is a lamp quality judgement apparatus and judgement method which judge quality by detecting the state of gas sealed in an electric lamp such as a gas-filled incandescent lamp, etc. in which gas with an Argon-Nitrogen mixture as its main component is sealed. More particularly, a lamp in which such gas is sealed is classified as a good product or as a bad product by imposing a high DC voltage or a high AC or pulsed voltage with a comparatively low frequency of 1 kHz or less across the lamp's valve and filament coil to produce discharge and emission, in the lamp, of a light in a wavelength region in the vicinity of 560 nm and judging the radiation state in this 560 nm light spectrum, i.e., the state of discharge in the lamp. The means employed for detecting the light spectrum radiation state include means for judging lamp quality by monitoring the temporal response characteristic in the light spectrum in the 560 nm wavelength region and means for effecting accurate judgement of lamps regardless of variations in the state of discharge in lamps by detecting the difference in intensity of the light spectra of two wavelength regions which are the light spectrum of a 560 nm w…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.