Optics: measuring and testing – By shade or color – Trichromatic examination
Patent
1997-04-25
1998-12-29
Evans, F. L.
Optics: measuring and testing
By shade or color
Trichromatic examination
356419, 356425, 101DIG45, G01J 351, G01N 2125
Patent
active
058546804
ABSTRACT:
A description is given of a photoelectric measuring device by means of which the light reflected from a measuring point on a printed product is detected, and the corresponding measured signals are processed for the purpose of indicating quality data. A measuring instrument of this type, having at least one illumination device and measuring channels, is an improvement over the prior art in order to expand its possible uses, with a construction which is cost-effective and stable when handled. In accordance with the invention, this is achieved with an illumination device which has a spectral intensity distribution which corresponds to the number of spectral ranges provided for the irradiation of the measuring point. The light from the sequentially drivable illumination devices irradiates the measuring point. The light reflected from the measuring point is detected and converted into a reflective signal which is processed to determine ink density values. The photoelectric measuring device is designed, in particular, as a densitometer, preferably being made using light-emitting diodes (LEDs). Interference filters are additionally used in order to match the spectral intensities of the diodes to the spectral ranges which are provided for obtaining ink density values.
REFERENCES:
patent: 4003660 (1977-01-01), Christie et al.
patent: 4681454 (1987-07-01), Breemer
patent: 4917500 (1990-04-01), Lugos
patent: 5117101 (1992-05-01), Moore et al.
patent: 5129726 (1992-07-01), Nielsen
Evans F. L.
MAN Roland Druckmaschinen
LandOfFree
Photoelectric densitometer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Photoelectric densitometer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photoelectric densitometer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1428001