Printer with automatic density adjusting function and density adjusting method of printer

• US 6,876,467 B1
• Filed: 08/15/2000
• Issued: 04/05/2005
• Est. Priority Date: 08/19/1999
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Yamaguchi, Yoshihiro
• Primary Examiner(s): Williams, Kimberly
• Assistant Examiner(s): BURLESON, MICHAEL L
• Application Number:
  US09/638,861
• Time in Patent Office: 1,694 Days
• Field of Search: 358/1.9, 358/3.1, 358/502, 358/503, 358/505, 358/504, 358/518, 347/19, 347/172, 347/175, 347/176
• US Class Current: 358/1.9
• CPC Class Codes: B41J 11/0095 Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end
• CPC Class Codes: B41J 29/393 Devices for controlling or analysing the entire machine ; Controlling or analysing mechanical parameters involving printing of test patterns
• CPC Class Codes: H04N 1/6033 using test pattern analysis H04N1/6055 takes precedence

Abstract

When densities of C, M and Y colors for automatic density adjustment are measured, test patterns of R, G and B colors are printed on TA paper, and a fixing lamp throws lights that have bright line spectrums of R, G and B colors onto the test patterns and amounts of reflected lights of the test patterns of R, G and B colors are measured with a light-receiving sensor that is an HP sensor for determining a reference position of the TA paper. Then, the densities of C, M and Y colors are calculated according to the amounts of the reflected lights. The color production of the C, M and Y layers of the TA paper is adjusted so that the calculated densities of C, M and Y colors are target densities.

Claims

1. A printer with an automatic density adjusting function that prints a color image on a color photographic paper that has a cyan (C) layer, a magenta (M) layer and an yellow (Y) layer by producing a color of each layer, said printer comprising:

a test pattern data producing device that produces test pattern data for printing test patterns of red (R), green (G) and blue (B) colors on said color photographic paper;

a printing device that prints the test patterns of R, G and B colors on said color photographic paper according to the test pattern data;

a light source that has bright line spectrums of R, G and B colors and throws lights onto the test patterns of R, G and B colors;

a light-receiving sensor that has spectral sensitivity characteristics in wavelength areas of R, G and B colors and measures amounts of reflected lights of the test patterns of R, G and B colors;

a density measuring device that measures densities of C, M and Y colors according to the amounts of the reflected lights of the test patterns of R, G and B colors that are acquired from said light-receiving sensor; and

an adjusting device that adjusts color production of the C, M and Y layers of said color photographic paper so that the measured densities of C, M and Y colors are target densities.

2. The printer with the automatic density adjusting function as defined in claim 1, wherein said light-receiving sensor also works as a home position sensor that detects a home position of the color photographic paper.

3. The printer of claim 1, wherein the R, G, B colors comprise individually formed color patches.

4. The printer of claim 1, wherein the color patches include formation of low density color patches formed of only two colors of C, M and Y which are formed at maximum density.

5. The printer with the automatic density adjusting function as defined in claim 1, wherein said light source is one of an M fixation fluorescent lamp and a Y fixation fluorescent lamp that is composed from fluorescent materials emitting the bright line spectrums of R, G and B colors.

6. The printer with the automatic density adjusting function as defined in claim 5, wherein said light-receiving sensor also works as a home position sensor that detects a home position of the color photographic paper.

7. The printer with the automatic density adjusting function as defined in claim 1, wherein:

said test pattern data producing device produces test pattern data on six test patterns that are test patterns of R, G and B colors with lowest densities and test patterns of R, G and B colors with reference densities; and

said density measuring device finds a ratio of an amount of a reflected light of the test pattern of R color with the lowest density to that of the test pattern of R color with the reference density, a ratio of an amount of a reflected light of the test pattern of G color with the lowest density to that of the test pattern of G color with the reference density, and a ratio of an amount of a reflected light of the test pattern of B color with the lowest density to that of the test pattern of B color with the reference density according to amounts of reflected lights of the six test patterns that are acquired from said light-receiving sensor and finds the densities of C, M and Y colors according to the found ratios.

8. The printer with the automatic density adjusting function as defined in claim 7, wherein the said light-receiving sensor also works as a home position sensor that detects a home position of the color photographic paper.

9. The printer with the automatic density adjusting function as defined in claim 7, wherein said light source is one of an M fixation fluorescent lamp and a Y fixation fluorescent lamp that is composed from fluorescent materials emitting the bright line spectrums of R, G and B colors.

10. The printer with the automatic density adjusting function as defined in claim 9, wherein said light-receiving sensor also works as a home position sensor that detects a home position of the color photographic paper.

11. A density adjusting method of a printer that prints a color image on a color photographic paper that has a cyan (C) layer, a magenta (M) layer and an yellow (Y) layer by producing a color of each layer, said density adjusting method comprising the steps of:

printing test patterns of red (R), green (G) and blue (B) colors on said color photographic paper;

sequentially throwing lights onto the test patterns of R, G and B colors with a light source that has bright line spectrums of R, G and B colors;

sequentially measuring amounts of reflected lights of the test patterns of R, G and B colors with a light-receiving sensor that has spectral sensitivity characteristics in wavelength areas of R, G and B colors;

calculating densities of C, M and Y colors according to the amounts of the reflected lights of the test patterns R, G and B colors; and

adjusting color production of the C, M and Y layers of said color photographic paper so that the calculated densities of C, M and Y colors are target densities.