Color sensor simulating standard source illuminant

Optics: measuring and testing – With plural diverse test or art

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

356328, 356407, 2504611, G01N 2127, G01N 2164

Patent

active

056421893

ABSTRACT:
Disclosed is an apparatus for measuring on-line the color and color-related properties of a moving sheet. Contrast ratio reflectance measurements are made for providing opacity corrections substantially in real time for a full color spectrum. An optical color sensor in accordance with the invention includes a pair of synchronized spectrometers, the first spectrometer being aligned to view a region of the sheet backed with a highly reflective ("white") material and the second spectrometer being aligned to view a region of the sheet backed with a highly absorptive ("black") material. The use of two spectrometers permits substantially simultaneous "black" and "white" measurements for a full color spectrum. The optical color sensing system further includes two light sources, a flashlamp and a continuously energized tungsten filament lamp. Light beams from the two sources are combined to form a sheet-illuminating third beam approximating the D65 standard source. The intensity of the flashlamp is electronically controlled to maintain the balance of UV to visible light that characterizes the standard source. The color sensor further includes a sheet backing system including a rotatable standard wheel carrying a white standard tile. Provision is made to permit rotation of the standard wheel and to standardize the sensor off-sheet while maintaining isolation of the white standard tile from the paper mill environment. The sheet backing system includes a paper guide plate defining an annular vortex space into which air is introduced from a pressurized source. A low pressure region thereby produced in the vortex space draws the paper sheet toward the guide plate. At the same time, circulating air spirals outwardly from the vortex space to form a thin air film or air bearing between the sheet and the paper guide. Sheet flutter is thereby minimized and damage to the sheet is prevented.

REFERENCES:
patent: 3936189 (1976-02-01), De Remigis
patent: 4277177 (1981-07-01), Larsen et al.
patent: 4641227 (1987-02-01), Kusuhara
patent: 4678338 (1987-07-01), Kitta et al.
patent: 4699510 (1987-10-01), Alguard
patent: 4715715 (1987-12-01), Howarth et al.
patent: 4919535 (1990-04-01), Hohberg et al.
patent: 4944594 (1990-07-01), Burk
patent: 5004349 (1991-04-01), Sato et al.
International Search Report, PCT Application No. PCT/US96/09738, International Filing Date Jun. 10, 1996, report dated Nov. 11, 1996.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Color sensor simulating standard source illuminant does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Color sensor simulating standard source illuminant, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color sensor simulating standard source illuminant will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-152084

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.