US5185644A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensor for water film on a plate in printing machines
Assignee: Mitsubishi Heavy Industries Ltd
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Filing: 1991-07-17
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Granted: 1993-02-09
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Expires: 2011-07-17
Abstract
Abstract An on-plate water film sensor for printing machines uses a narrow-band light source, a photo modulator for chopping a light beam therefrom into p- and s-polarized beams, a collimator for making parallel the rays of the collimated beams with a given cross-sectional area for measurement, a wavelength plate for adjusting the wavefront of the parallel rays, a receiver for the light secularly reflected from a plate, and an arithmetic unit to figure out the thickness of a water film formed on the plate based on the intensities of the received beams. Water lining which usually has patterns of narrow width can be detected, and the measurement of a water film thickness can be done with high speed.
Inventors
- 👤 Makoto Shimoyama
- 👤 Ikuo Ozaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:41
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/02; G01B11/06; G01B11/0616; G01B11/0641; G01B11/065; Y; Y10; Y10S; Y10S101/00; Y10S101/45
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
110 words
A sensor for measuring the thickness of a water film formed on a plate in a printing machine, comprising a narrow-band light source, a photo modulator for alternatively chopping light from the light source into p-polarized and s-polarized beams, a collimator for making rays of the chopped beams parallel to each other with a given cross-sectional area for measurement, a wave-length plate for adjusting wavefront of the collimated parallel rays and directing the parallel rays onto the water film at a selected angle of incidence, and a device for receiving light beams reflected specularly from the plate and for calculating the thickness of a water film formed on the plate.
Claim 2
Dependent Claim
110 words
A sensor for measuring the thickness of a water film formed on a plate in a printing machine, comprising a narrow-band light source, a photo modulator for alternatively chopping light from the light source into p-polarized and s-polarized beams, a collimator for making rays of the chopped beams parallel to each other with a given cross-sectional area for measurement, a wave-length plate for adjusting wavefront of the collimated parallel rays and directing the parallel rays onto the water film at a selected angle of incidence, and a device for receiving light beams reflected specularly from the plate and for calculating the thickness of a water film formed on the plate.
Claim 3
Dependent Claim
18 words
The sensor as defined in claim 1, wherein said photo modulator is a chopper using an electro-optical effect.
Claim 4
Dependent Claim
28 words
The sensor as defined in claim 1, wherein the angle of incidence of the collimated parallel rays and a plane perpendicular to the plate is a Brewster angle.
Claim 5
Dependent Claim
20 words
The sensor as defined in any one of claims 1 to 3, wherein said narrow-band light source is a laser.
Claim 6
Dependent Claim
23 words
The sensor as defined in any one of claims 1 to 3, wherein said narrow-band light source is a light emitting diode (LED).
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-02-09 | 1996-08-10 | 1997-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-02-09 | 2000-08-10 | 2001-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-02-09 | 2004-08-10 | 2005-02-09 | $7700.00 | Window Closed / Lapsed |