Colorimeter apparatus for color printer ink

• US 20030058447A1
• Filed: 08/08/2002
• Published: 03/27/2003
• Est. Priority Date: 08/14/2001
• Status: Abandoned Application

• Current Assignee: Nireco Corporation
• Original Assignee: Nireco Corporation
• Inventors: Kobayashi, Tomoyuki, Yamada, Takeo
• Application Number:
  US10/215,102
• Publication Number:
  US 20030058447A1
• Time in Patent Office: Days
• US Class Current: 356/402
• CPC Class Codes: G01J 2003/466 Coded colour; Recognition of predetermined colour; Determining proximity to predetermined colour
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0208 using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/024 using means for illuminating a slit efficiently (e.g. entrance slit of a spectrometer or entrance face of fiber)
• CPC Class Codes: G01J 3/26 using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters
• CPC Class Codes: G01J 3/465 taking into account the colour perception of the eye; using tristimulus detection
• CPC Class Codes: G01J 3/51 using colour filters
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs

Abstract

The present invention provides a colorimeter apparatus for a color printer ink capable of rapidly measuring the colors of a color patch portion in an online mode. The light of a xenon light source 21 is directed via an optical fiber 22 and a condenser lens 23 to a zone through which a color patch 53 passes. Reflected light is condensed by a telecentriclens system 14 and focused on the light-receiving surface of a Linear Variable Filter 11. The light is spectrally divided by the Linear Variable Filter 11 and guided toward a linear sensor 13 via a fiber optic plate (FOP) or collimator 12. The output of the linear sensor 13 is converted to an analog signal by an analog signal generator 14 and sent to a signal processor 3. In the signal processor 3, a spectral reflectance factor is calculated based on the resulting spectral reflectivity, and a color or color difference is calculated based on this value and a prestored formula for color systems or color differences.

Claims

1. A calorimeter apparatus for a color printer ink designed to measure the ink color of a color printer in which a color patch is also printed on a print in order to identify the ink color, said apparatus comprising at least one light irradiation means for directing light at a specific angle to a specific irradiation area in the passing zone of a color patch on a moving print;

a spectral unit including a spectral sensor and an optical system for measuring the spectral reflection intensity of light reflected from the irradiation area;

spectral reflectance factor calculation means for calculating a spectral reflectance factor on the basis of signals from the spectral unit; and

a signal processor for calculating a color or color difference on the basis of the calculated spectral reflectance factor and a stored formula for color systems or color differences, wherein the spectral unit has a Linear Variable Filter, a fiber optic plate or collimator, and a linear sensor.

2. The calorimeter apparatus for a color printer ink according to claim 1, wherein the spectral unit operates such that light reflected by the irradiation area is received by a telecentric lens system having an optical power of 4 or greater with a measurement distance of 65 mm or greater.

3. The calorimeter apparatus for a color printer ink according to claim 1, wherein the light irradiation means uses a xenon light source as the light source.

4. The calorimeter apparatus for a color printer ink according to claim 1, wherein the light irradiation means has an optical fiber for guiding the light of the light source, and a condenser lens provided at the tip of the optical fiber on the side facing the print.

5. The colorimeter apparatus for a color printer ink according to claim 1, wherein said light irradiation means comprises a light splitter for dividing in two the light output of the light source in the light irradiation means;

one of the two divided light beams is directed to the passing zone of the color patch on the moving print;

the other light beam is guided toward a light source emission spectrum measuring apparatus for measuring the emission spectrum of the light source; and

the spectral reflectance factor calculation means has a function whereby the signal of the spectral unit is corrected using the signal from the light source emission spectrum measuring apparatus, and a spectral reflectance factor is calculated.

6. The calorimeter apparatus for a color printer ink according to any of claim 2, wherein said light irradiation means comprises a light splitter for dividing in two the light output of the light source in the light irradiation means;

one of the two divided light beams is directed to the passing zone of the color patch on the moving print;

the other light beam is guided toward a light source emission spectrum measuring apparatus for measuring the emission spectrum of the light source; and

the spectral reflectance factor calculation means has a function whereby the signal of the spectral unit is corrected using the signal from the light source emission spectrum measuring apparatus, and a spectral reflectance factor is calculated.

7. The calorimeter apparatus for a color printer ink according to any of claim 3, wherein said light irradiation means comprises a light splitter for dividing in two the light output of the light source in the light irradiation means;

one of the two divided light beams is directed to the passing zone of the color patch on the moving print;

the other light beam is guided toward a light source emission spectrum measuring apparatus for measuring the emission spectrum of the light source; and

the spectral reflectance factor calculation means has a function whereby the signal of the spectral unit is corrected using the signal from the light source emission spectrum measuring apparatus, and a spectral reflectance factor is calculated.

8. The calorimeter apparatus for a color printer ink according to any of claim 4, wherein said light irradiation means comprises a light splitter for dividing in two the light output of the light source in the light irradiation means;

one of the two divided light beams is directed to the passing zone of the color patch on the moving print;

the other light beam is guided toward a light source emission spectrum measuring apparatus for measuring the emission spectrum of the light source; and

the spectral reflectance factor calculation means has a function whereby the signal of the spectral unit is corrected using the signal from the light source emission spectrum measuring apparatus, and a spectral reflectance factor is calculated.