Optics: measuring and testing – Of light reflection – With diffusion
Patent
1988-04-28
1990-07-31
McGraw, Vincent P.
Optics: measuring and testing
Of light reflection
With diffusion
356429, 356434, 356 73, G01J 342
Patent
active
049445944
ABSTRACT:
Apparatus (10) and methods for measuring dark and bright reflectances of translucent sheet material (2) are disclosed. The apparatus (10) comprises first optical means for illuminating one side of the sheet material (2) with a source of electromagnetic radiation. A portion of the radiation is transmitted through the sheet material (2) and another portion of the radiation is reflected by the sheet material. The apparatus (10) also comprises optical gating means (30) that is positioned adjacent the other side of the sheet material (2) in a fixed position relative to the first optical means. The optical gating means (30) absorbs substantially all of the transmitted portion of the radiation when switched to a dark state and reflects substantially all of the transmitted portion of the radiation back through the sheet material (2) when switched to a bright state. The apparatus (10) further comprises second optical means for collecting the reflected portion of the radiation and the portion of the transmitted portion of the radiation reflected by the optical gating means (30) and retransmitted through the sheet material (2) to provide a total reflectance. The total reflectance has a dark reflectance intensity when the optical gating means (30) is in the dark state and a bright reflectance intensity when the optical gating means is in the bright state. The apparatus also comprises sensing means (60), responsive to radiation collected by the second optical means, for providing a dark signal having a magnitude corresponding to the dark reflectance intensity and a bright signal having a magnitude corresponding the bright reflectance intensity. The dark and bright signals can be incorporated in known formulae to compute values for quality attributes of the sheet material (2) including opacity and color.
REFERENCES:
patent: 1950975 (1934-03-01), Davis
patent: 3455637 (1969-07-01), Howard
patent: 3936189 (1976-02-01), DeRemigis
patent: 4076421 (1978-02-01), Kishner
patent: 4224513 (1980-09-01), Casey
patent: 4589735 (1986-08-01), Saunders
patent: 4624572 (1986-11-01), van den Bosch
patent: 4678325 (1987-07-01), Lehtikoski et al.
patent: 4715715 (1987-12-01), Howarth et al.
McGraw Vincent P.
Process Automation Business Inc.
Turner S. A.
LandOfFree
Apparatus and method for measuring dark and bright reflectances does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for measuring dark and bright reflectances , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for measuring dark and bright reflectances will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1395591