JP2000355119A - Method for inspecting projection amount of light of print head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate specifying by which light projection elements on a head each of unit images for inspection is formed, by relating a density read value of the unit image for inspection in each pattern for density inspection to a corresponding address in an array of light projection elements on the basis of information from an auxiliary pattern for element specification. SOLUTION: A dot pattern Dp4 for detecting an emission quantity of light is composed of dot patterns DpR1, DpR2, DpG and DpB formed by phosphor elements. Each pattern has a pattern for density inspection and an auxiliary pattern. The pattern for density inspection includes a first-a third dot faces DF1-DF3 arranged in parallel in a sub scanning direction. The auxiliary pattern includes a color index pattern iDC, patterns iDs for sub scanning index and auxiliary patterns iDm for element specification. The auxiliary patterns iDm help to recognize information on addresses in an array of the phosphor elements via a line scanner and relate a density read value of a unit image for inspection to the corresponding address in the array of the phosphor elements.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting a light emitting amount of a print head for exposing a photosensitive material on the basis of required image information, and more specifically, to a method of inspecting light emitting elements forming a print head. In order to inspect the variation of the light emission amount, etc., the individual light emission amounts of the plurality of light emission elements arranged in a row along the main scanning direction on the print head are used for the light emission of the individual light emission elements. The present invention relates to a method for inspecting the light emission amount of a print head for inspecting based on the density of a unit image for inspection formed on a photosensitive material based on the information.

[0002]

2. Description of the Related Art The above-mentioned method for inspecting the light emission amount of a print head is disclosed in the
Japanese Patent Application No. 9-361157, filed on June 6, is known. As shown in FIG. 13-A of the accompanying drawings of the present application and FIG.
Dot-shaped images corresponding to the individual phosphor elements constituting the print head to be inspected are arranged in a row at intervals along the main scanning direction, and also form a plurality of rows separated from each other in the sub-scanning direction. The first step of exposing and outputting a photosensitive material as an inspection pattern composed of dots (actually,
And a second step of measuring the density of each dot of the dot pattern Dp2 thus obtained on the photosensitive material with a scanner for each row. I have. By adopting this method, rows of dots spaced apart in the main scanning direction are formed (actually, one row Do is formed by simultaneous light emission of light emitting elements at odd addresses and the other row is formed by simultaneous light emission). De is formed by simultaneous light emission of the light emitting elements at the even addresses), so that there is no overlap between the dots in the main scanning direction. Therefore, when this is scanned by a scanner, the individual densities of the dots can be measured without being affected by other dots. Moreover, the rows of the dots are arranged in the sub-scanning direction (FIG. 13).
In the following process, the scanning operation by the line scanner or the like can be separated into several scanning operations divided for each column, and these several scanning operations can be combined. In this case, the density measurement of all dots is covered. As a result, the intended purpose of accurately grasping the light emitting state of each light emitting element can be easily achieved. If the print head is composed of blocks for R (red), G (green), and B (blue), the above-described steps are performed for each of these blocks. The light emitting state can be inspected for all the light emitting elements to which the print head is attached.

[0003] However, the above-mentioned Japanese Patent Application No. 9-3611 is disclosed.
According to the method described in No. 57, when analyzing density information obtained by a scanner, an individual inspection unit image in each of the density inspection patterns and an address of the light emitting element in which the Since the correspondence relationship with the information is unclear, for example, when a light emitting element with a short light emitting amount is found as a result of the inspection, it is not possible to accurately specify which light emitting element in the row corresponds to the light emitting element. A case has arisen.

[0004]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method for inspecting the amount of light emitted from a print head according to the prior art, which has been described above. Provided is a method for inspecting a light emission amount of a print head, which makes it easy to identify which light emitting element formed on the print head causes each unit image for inspection.

[0005]

In order to achieve the above object, a method for inspecting the light emission state of a print head according to the present invention comprises:
It has the features described in each claim of the claims. Incidentally, the method for inspecting a light emission state of a print head according to claim 1 of the present invention is characterized by comprising the following steps. <1> A predetermined light emission amount inspection dot pattern is exposed by the print head. A first step of forming on a material, wherein the predetermined light emission amount inspection dot pattern is a density inspection pattern obtained by collecting the inspection unit images formed by the light emission elements, and In order to identify the address information in the row of the light emitting elements that formed the individual inspection unit images in each density inspection pattern area, the specific inspection unit image in each density inspection pattern area was specified. <2> a second step of simultaneously taking in the density inspection pattern and the element specifying auxiliary pattern with a scanner, including an element specifying auxiliary pattern provided adjacently. And <3>, based on the information obtained from the element specifying auxiliary pattern, the density reading value of each inspection unit image in each of the density inspection patterns, the address of the corresponding light emitting element in the column. Third step to associate.

[0006] In order to have such a characteristic configuration,
In the method for inspecting the light emission state of a print head according to claim 1 of the present invention, an auxiliary pattern for element identification is provided separately from the specific unit image for inspection in each of the density inspection patterns. At the same time as capturing the density inspection pattern, the element identification auxiliary pattern can also be captured.Based on the information obtained from the element identification auxiliary pattern, the inspection head output on the photosensitive material by the print head is used. , It is always possible to accurately specify which of the light emitting elements formed on the print head all the unit images are.

The print head is provided with light emitting elements having different emission light colors in the row for each color, and the element specifying auxiliary pattern for each color is a density inspection pattern for each color. It is possible to adopt a configuration including dots of the same color as the corresponding density inspection pattern formed adjacent to the inspection unit image by a part of the light emission elements formed with. With this configuration, the element specifying auxiliary pattern serves as an index that more correctly indicates the position of each inspection unit image in each density inspection pattern adjacent thereto. That is, R
In the case where light-emitting elements having different emission light colors are provided in a row for each color, such as GB, if the light-emitting elements of each color located at the same address of the row of each color are all emitted at the same location,
It is possible to form an auxiliary pattern for element identification having a very high density (showing black as a whole). However, the light emitting elements of different colors are located at the same address of each row of RGB, but are more or less shifted in the main scanning direction of the print head due to a manufacturing error of the print head. Tend. In this case, at first glance, the width of the black high-density element specifying auxiliary pattern in the main scanning direction, as a whole, exceeds the width of the actually adjacent specific inspection unit image to be represented and is excessively large. It has a wide width. As a result, the element specifying auxiliary pattern does not correctly represent the position of the adjacent specific inspection unit image, and there is a possibility that correct address information may not be recognized at the time of capturing by the scanner. Was. However, according to the configuration of the present application, each of the element specifying auxiliary patterns is formed only by a part of the light emitting element on which the density inspection pattern is formed. The position of the unit image for inspection and the width in the main scanning direction are directly reflected, and the address in the row on the print head of the light emitting element that has formed the adjacent unit image for inspection is accurately specified. be able to.

More specifically, the part of the light emitting elements on which the element specifying auxiliary patterns are formed is one light emitting element arranged at the center in the main scanning direction on the print head. A certain configuration may be used.

Further, the plurality of light emitting elements are arranged in a row along the main scanning direction of the print head for each of the emitted light colors of RGB to constitute a linear print head. What is necessary is just to comprise so that a movement operation with respect to a photosensitive material may be carried out in the sub scanning direction.

[0010] Further, the first step is performed by adjusting the print head so that the inspection unit image and the element specifying auxiliary pattern form a plurality of dot images arranged linearly in the sub-scanning direction. What is necessary is just to carry out while moving in the sub scanning direction. According to this structure, an error is less likely to occur in the data acquisition by the scanner in the second step. Alternatively, if the light receiving elements arranged in a line on the scanner are scanned so as to be parallel to the straight line of the inspection unit image and the element specifying auxiliary pattern, the light receiving elements on the scanner can be scanned. Therefore, it is possible to capture at the same time a plurality of pieces of data relating to the light emission amount of each light emitting element carried by one inspection unit image and the element specifying auxiliary pattern, so that more accurate information can be captured. Become.

Other features and advantages according to the present invention will become apparent from the following description of embodiments with reference to the drawings.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. (Structure of Fluorescent Printhead) FIG. 1 is a schematic sectional view of a fluorescent printhead 60 for color printing used in a fluorescent printer according to the present invention. The fluorescent printhead 60 is actually R1 (red), R2 (red),
G (green), B (blue) four light-emitting blocks 32, 33,
34 and 35 (see FIG. 4), but here R1
Only the light-emitting block 32 is shown. The other three light emitting blocks 32, 33, 34 have the same configuration.
It should be noted that only the red light (R) is composed of two blocks in order to balance the density of the image formed on the photographic paper with the other green and blue colors. A first strip-shaped anode electrode 62 and a second strip-shaped anode electrode 63 made of an aluminum thin film are formed on the inner surface of a substrate 61 made of a light-transmitting material, which constitutes the light-emitting block 32. As shown in FIG. 2, the two strip-shaped anode electrodes 62 and 63 move in the transport direction of a photosensitive material (hereinafter, simply referred to as photographic paper) 3 such as photographic paper exposed by the fluorescent print head 60. The rectangular transmission holes 62a and 63a are provided at a predetermined pitch while extending in the main scanning direction at a right angle. Transmission hole 62a of first belt-shaped anode electrode 62
The transmission holes 63a of the second strip-shaped anode electrode 63 are arranged in a staggered pattern as shown in FIG. Each transmission hole 62
The phosphors 64 a and 63 a are, for example, coated with a phosphor 64 mainly composed of Zn: ZnO. A plurality of phosphors 64 corresponding to the phosphor 64 are provided at intervals from the phosphor 64 in a direction crossing the main scanning direction. A grid electrode 65 extends. In the grid electrode 65, a slit hole 65a as a light transmitting portion is formed in an area facing the phosphor 64. The grid electrodes 65 are electrically independent of each other, and an independent control voltage is applied to each of them. Grid electrode 65
Further, an acceleration electrode 66 is provided further away from. The accelerating electrode 66 is formed by a slit hole 65a of the grid electrode 65.
, And a common acceleration voltage is applied thereto. Further, a linear cathode electrode 67 as a filament is provided at a position away from the grid electrode 65 along the main scanning direction.

The phosphor 64 and the first strip-shaped anode electrode 62
Alternatively, the second strip-shaped anode electrode 63 and the grid electrode 65
And the accelerating electrode 66 constitute each phosphor element F (an example of a light emitting element), and the light irradiated by each phosphor element F forms a one-dot latent image on the printing paper 3. And
As will be described later, the phosphor element F provided on the first strip-shaped anode electrode 62 constitutes an odd pixel of the print head (meaning an odd-numbered pixel from the end of the print head), and the second strip-shaped anode electrode The phosphor element F provided in 63 constitutes an even pixel (meaning an even-numbered pixel from the end of the print head). As a result, the phosphor elements F are arranged in a row along the main scanning direction as a whole (specifically, a row of odd pixels and a row of even pixels are adjacent to each other in the sub-scanning direction). Arranged in two rows). As described above, the strip-shaped anode electrodes 62 and 63, the grid electrode 65, and the acceleration electrode 6
6, the cathode electrode 67 is formed between the inner surface of the substrate 61 and the cover body 6.
It is housed in a vacuum space created by 8. A red filter 69 as a color filter is provided on the outer surface of the substrate 61 so as to face the phosphor 64. The light beam 70 emitted from the phosphor 64 is applied to the red filter 6.
The light is adjusted at 9, and an image is formed on the photographic paper 3 (an example of a photosensitive material) by the SELFOC lens 71. Cathode electrode 67
While a predetermined voltage is applied to the acceleration electrode 66 and a predetermined voltage, a voltage is alternately applied to the first band-shaped anode electrode 62 and the second band-shaped anode electrode 63 at a predetermined timing, and a desired grid electrode 65 is synchronized with this timing. By applying a positive exposure signal to, the thermoelectrons jumping out of the cathode electrode 67 pass through the slit holes 65 a according to the state of the grid electrode 65 and collide with the phosphor 64. Phosphor 6 hit by thermal electrons
Reference numeral 4 radiates light, and the light beam 70 passes through the transmission hole and reaches the photographic paper 3, thereby exposing the photographic paper 3 to light beam dots.

Since the emission characteristics of the individual phosphor elements F vary in the emission area of the phosphor, the distance between the electrodes, and the like, each phosphor element F is operated under the same driving conditions.
The control signal sent to the grid electrode 65 is corrected based on the light emission amount value actually measured under the same driving conditions in advance so that the light amounts of the light beams become the same. Thereby, each phosphor element F
The variation in the amount of light emitted from the at least for each light-emitting block of each color, or within the entire print head,
Can be minimized. Incidentally, the light emission amount value required for the above correction can be obtained exactly by the method for inspecting the light emission amount of the print head according to the present invention, which will be described in detail later. In addition, a control signal corrected based on the light emission amount value actually measured under the same driving condition in advance is sent to the grid electrode 65 to drive the fluorescent print head, and each of the phosphor elements F of which the light amount is made uniform. The operation for checking the output state (whether or not it is truly uniform) also uses the method for inspecting the light emission amount of the print head according to the present invention.

(Reciprocating Mechanism of Fluorescent Printhead) As shown in detail in FIG. 3, the fluorescent printer 30 includes a light emitting block 32 of R1 having the above-described structure, and a light emitting block R2 of the same basic structure as R1. Light emitting block 33,
G light-emitting block 34 and B light-emitting block 35
And a reciprocating mechanism 50 for scanning the fluorescent print head 60 in the conveying direction of the printing paper 3. Fluorescent print head 6
0 are connected to the controller 7 shown in the block diagram of FIG. 6, and the light-emitting blocks 32, 33, 34, and 35 of FIG.
The drive system of the reciprocating mechanism 50 is connected to the sub-controller 107. Image data and characters are controlled based on emission control of the phosphor element F in the main scanning direction by the controller 7 and scanning control of the fluorescent print head 60 in the sub-scanning direction by the sub-controller 107 via the reciprocating mechanism 50. The data can be color-exposed on the photographic paper 3. Since the paper mask 40 has a known structure, a detailed description is omitted. However, as schematically shown in FIGS. 4 and 5, the paper mask 40 mainly extends in parallel to the transport direction of the base 45 and the printing paper 3. An upper side member 41 and a lower side member 42, and a left side member 43 and a right side member 44 extending in the transverse direction of the photographic paper 3 in the transport direction. Upper side member 41 and lower side member 42
Are supported on a base 45 so as to be movable in the transverse direction of the transport direction, while the left side member 43 and the right side member 44 are supported on the base 45 so as to be able to reciprocate in the transport direction.
By controlling the distance between the upper side member 41 and the lower side member 42, the exposure range in the width direction of the printing paper 3 is changed to the left side member 43 and the right side member 44.
, The exposure range in the length direction of the printing paper 3 can be changed. Upper side member 41, lower side member 42, left side member 4
3. The movement of the right side member 44 is controlled by the controller 7 via a drive mechanism (not shown).

A reciprocating mechanism 50 for the fluorescent print head 60 is mounted on the base 45 of the paper mask 40, and its basic components are guides provided at both ends of the fluorescent print head 60. A member 51, a guide rail 52 inserted through a guide hole 51 a provided in the guide member 51, a pair of sprockets 55 arranged at both ends of the base 45, a wire fastener 53 provided in one guide member 51, The wire 54 is wound between a pair of sprockets 55 and both ends are fixed to the wire fastener 53. The pulse motor 56 rotates the one sprocket 55 forward and backward under the control of the sub-controller 107. The rotation operation of the pulse motor 56 moves the fluorescent print head 60 in the sub-scanning direction along the guide rail 52 through the rotation of the wire 54. That is, as described above, the phosphor elements F are arranged in two rows slightly separated in the sub-scanning direction for each emission color in order to substantially increase the degree of integration in the main scanning direction. In a normal exposure operation based on image information (except for the inspection operation described below), for example, even if all the odd and even phosphors 64 emit light, the print head 60
And the photographic paper 3 are moved relative to each other in synchronization with the temporal shift of the light emission set between the phosphors 64 in the odd-numbered rows and the phosphors 64 in the even-numbered rows. The image exposed in step 2 is not a two-row image separated in the sub-scanning direction, but a one-row image.

(Exposure Control of Photographic Paper by Fluorescent Printhead) FIG.
FIG. 3 is a schematic block diagram schematically illustrating exposure control of FIG.
The controller 7 has an input port for inputting image data output from a recording medium such as a magnetic disk, a CD-ROM, or a device capable of inputting and outputting digital images, such as a digital camera, a scanner, and a computer. 7a, an image processing unit 7b that performs image processing on input image data and bit-character data, and also generates luminance data divided into 256 levels (8 bits) in dot units, and sets driving conditions for the fluorescent print head 60 And a printer control unit 7c. The printer control unit 7c includes a cathode control unit 91 that controls a cathode voltage, and a grid control unit 92 that controls a grid voltage.
And an anode control unit 93 for controlling an anode voltage. The anode control unit 93 sends an applied voltage value suitable for the type of the printing paper 3 to be printed to the print head driver 7f. Thereby, each anode electrode 62 and 6 of each light emitting block 32, 33, 34, 35
An anode voltage that emits light optimal for the printing paper 3 to be printed is applied to 3. Grid control unit 9
2 sends the image data obtained from the image processing unit 7b to the print head driver 7f. The luminance value of each color sent to the print head driver 7f is converted into a drive pulse width there, and the R1 light emitting block 32, the R2 light emitting block 33, the G light emitting block 34,
It is sent to each grid electrode 65 of the B light emitting block 35.
Further, the controller 7 is provided with a communication port 7g, which is a communication port 10g of the sub-controller 107.
7a. In the sub-controller 107,
A sub-controller 107 is provided in cooperation with the controller 7 to generate a control signal relating to the scanning speed and timing of the fluorescent print head 60. The sub-controller 107 is connected to the output port 107c and the motor driver 107d.
, A control signal is sent to a pulse motor 56 for moving the fluorescent print head 60 in the sub-scanning direction. By the cooperation of the controller 7 and the sub-controller 107, image printing is performed by the fluorescent print head 60 on a predetermined position of the photographic paper 3.

(Light Emission Inspection Method) Next, an embodiment of a light emission amount inspection method for a print head according to the present invention will be described using the above-described fluorescent print head 60 for color printing as an example. FIG. 7 shows the R1 of the fluorescent print head 60.
It is a schematic plan view showing the whole (red) light-emitting block 32. The other three light-emitting blocks 33, 34, and 35 of R2 (red), G (green), and B (blue) have the same structure, and therefore, exactly the same light-emitting state inspection method can be applied. . As described above, the light-emitting block 32
Has a first strip-shaped anode electrode 62 and a second strip-shaped anode electrode 63 extending in the main scanning direction, and the phosphor elements F provided on the first strip-shaped anode electrode 62 constitute odd pixels of a print head. And the second strip-shaped anode electrode 63
The phosphor element F provided in the above constitutes an even pixel. Then, all odd pixels formed by the phosphor elements F provided on the first strip-shaped anode electrode 62 and all even pixels formed by the phosphor elements F provided on the second strip-shaped anode electrode 63 are compared with each other based on image information. Exposure to the same position in the sub-scanning direction on the photographic paper as in the exposure operation described above results in the formation of a line dot pattern in a row that is not separated from each other in the sub-scanning direction. In such a dot pattern, dots adjacent in the main scanning direction partially overlap each other in the outermost region, and the density of each dot is read by a scanner or the like to inspect the light emitting state of each phosphor element. Then, it is difficult to accurately grasp the light emitting state of each phosphor element F due to the influence of another adjacent dot D. Therefore, in the print head light emission amount inspection method according to the present invention, first,
By causing the phosphor elements F of the print head to emit light in the following manner, a special light emission amount inspection dot pattern is formed on the photographic paper by exposure, and then, after the photographic paper is developed, the inspection dot pattern is formed. Is read by a scanner to determine the emission characteristics of each phosphor element F. As the above-mentioned dot pattern, the dots D as the density test target obtained by the individual phosphor elements F selected as the test target elements are not adjacent to each other in the main scanning direction of the print head 60, and the density At the time of measurement, the light of the scanner is not flared into the area of the dot D as the density inspection
A pattern in which the periphery of the dot D as a density inspection target is filled with a predetermined density is adopted.

The specific light emission amount inspection includes the following first to third steps.
The process is performed according to each process up to. <First Step> A predetermined light emission amount inspection dot pattern is formed on a photosensitive material by the print head 60. The light emission amount inspection dot pattern includes a density inspection pattern and an element identification auxiliary pattern. <Second step> The dot pattern for light emission amount inspection is captured at once by a scanner. As a result, the density test pattern and
The auxiliary pattern for element identification included in the auxiliary pattern is simultaneously captured. <Third step> Based on information obtained from the element specifying auxiliary pattern and other auxiliary patterns, the density read values of the individual inspection unit images in each density inspection pattern are stored in the corresponding light emitting element columns. Associate with the address in.

(Details of Light Emission Inspection Dot Pattern) FIG. 8 shows an example of the predetermined light emission amount inspection dot pattern formed on one sheet of photographic paper based on the first step. The dot pattern Dp for light emission amount inspection described here
4 is an R1 dot pattern DpR1 formed by the phosphor elements F on the R1 light-emitting block 32;
R2 dot pattern DpR by light emitting block 33
2. G dot pattern Dp by G light emitting block 33
It is composed of a dot pattern DpB for B by the G and B light-emitting blocks 34. However, the light emission amount inspection dot pattern Dp4 divided into these four blocks is formed by exposing and developing the fluorescent print head 60 on the photographic paper stationary on the paper mask 40 by one moving operation. It is. More specifically, for example, the R1 dot pattern DpR1 includes a density inspection pattern and an auxiliary pattern. However, the same applies to the other dot patterns DpR2, DpG, and DpB.

(Density Inspection Pattern) The density inspection pattern for R1 is obtained by gathering inspection unit images formed by the phosphor elements F having the emission color of R, and is mutually sub-scanned. 1st dot surface DF arranged side by side
1, a second dot surface DF2, and a third dot surface DF3. First, second and third dot surfaces DF1, DF2, DF
3 shows a cyan color after the development processing based on the latent image obtained by the R1 red exposure, and has a length of about 7 mm in the sub-scanning direction. As shown in FIG. 9 in which the circle P in FIG. 8 is enlarged, the first dot surface DF1 drives the fluorescent print head 60 in the sub-scanning direction while the even-numbered phosphors are synchronized with this driving. A high-density linear measurement dot DLe (a region indicated by crossed oblique lines by a group of horizontally arranged dots) formed by causing all of the elements F to emit light under a high predetermined density condition for inspection; Simultaneously with the light emission of the phosphor element F, a line-shaped background dot BgLo formed by causing all of the odd-numbered phosphor elements F to emit light at a density condition of 50 to 60% of the inspection dot.
(Regions indicated by diagonal lines inclined downward and left by horizontally arranged dot groups). Both the line-shaped measurement dots DLe and the line-shaped background dots BgLo extend in the sub-scanning direction with a length of about 7 mm in order to facilitate reading of dots by the line scanner 80 in the second step. The second dot surface DF2 is formed by driving the fluorescent print head 60 in the sub-scanning direction and causing all the phosphor elements F to emit light under the same high predetermined density condition as that for the inspection while being synchronized with the driving. (The area indicated by crossed oblique lines). Third dot surface DF3
Indicates that while driving the fluorescent print head 60 in the sub-scanning direction in a manner opposite to that of the first dot surface DF1, all of the odd-numbered phosphor elements F are synchronized with this driving and have a high predetermined density for inspection. High-concentration line-shaped measurement dots DLo formed by emitting light under the conditions (by a group of dots arranged horizontally,
All the even-numbered phosphor elements F were formed to emit light under the density condition of 50 to 60% of the inspection dots at the same time as the light emission of the odd-numbered phosphor elements F. And a line-shaped background dot BgLe (a region indicated by a diagonally downward slanted line formed by a group of horizontally arranged dots). The density data finally required by this inspection method is the linear measurement dot DL in the first dot surface DF1.
e and the linear measurement dot D in the third dot surface DF3
Only Lo (these are examples of inspection unit images). The line-shaped background dots BgLo and the line-shaped background dots BgLe are read by the scanner in the second step so that flare from the reading auxiliary light does not prevent the reading of the line-shaped measurement dots DLe and DLo. It is formed for the purpose of controlling the reflectance of an unnecessary portion on the photographic paper. When the inspection dot pattern Dp2 is scanned in the sub-scanning direction by the line scanner 80, the second dot surface DF2 is shifted from the first dot surface DF1 in which the area being scanned includes the even-numbered linear measurement dots DLe. Alternatively, it serves to indicate to the scanner that it has escaped from the third dot surface DF3 including the odd-numbered linear measurement dots DLo (in the case where scanning is performed in the sub-scanning direction in the direction opposite to the arrow in FIG. 12). .

(Auxiliary Pattern) The auxiliary pattern iD includes
In order to define to the scanner which of the light emitting blocks R1, R2, G, and B the dot pattern is adjacently arranged, a color index pattern iDC formed at an end in the photographic paper transport direction, a sub-scanning direction A sub-scanning index pattern iDs for positional information about the element and an element identifying auxiliary pattern iDm for positional information about the main scanning direction are included.

{Color Index Pattern iDC} The color index pattern iDC indicating that the dot pattern for R1 is adjacently arranged is a single thin black line (having a width of about 0.2 mm) extending over the entire length in the main scanning direction. ). This is obtained by causing the corresponding phosphor elements F on the R1 light-emitting block 32, the R2 light-emitting block 33, the G light-emitting block 34, and the B light-emitting block 35 to emit light uniformly. Note that R
2 is two thin black lines, G is three, and B is four black lines. {Sub-scanning index pattern iDs} The sub-scanning index pattern iDs is a black line that also extends along the main scanning direction of the print head, but is a line having a width of about 2 mm, which is much thicker than the color index pattern iDC. It is.

{Element Identifying Auxiliary Pattern iDm} The element identifying auxiliary pattern iDm is composed of individual linear measurement dots DLe and DLo (that is, individual dots) in the density inspection pattern.
The address information in the column of the phosphor elements F on which the inspection unit images are formed is recognized through the line scanner 80, and the "density read value of the inspection unit images is converted to the corresponding light emitting element in the third step. This is a pattern arranged adjacent to each of the first dot surface DF1 and the third dot surface DF3. Actually, it is formed by exposing only one phosphor element F located at the center of each light emitting block in the main scanning direction. As shown in FIG. 10 in which a circle Q in FIG. 8 is enlarged, here, the element identifying auxiliary pattern iDm is
This corresponds to the phosphor element F for even pixels. Therefore, the element identification auxiliary pattern iDm formed adjacent to the first dot surface DF1 on the left side of FIG.
e, the auxiliary pattern for element identification formed adjacent to the third dot surface DF3 is connected to the right end of the line-shaped background dot BgLe. This extends so as to connect the left sub-scanning index pattern iDs. A total of eight element identification auxiliary patterns iDm are provided, each having a length of 2 to 3 mm in the sub-scanning direction. As described above, the element specifying auxiliary pattern iDm is formed by exposing only the phosphor element F at the center on the light-emitting block. It is the same as the inspection unit image. Further, for the same reason, the element specifying auxiliary pattern iDm is formed in a unique color of the corresponding light emitting block. That is, the dot pattern D for R1 and R2 for the R1 and R2 light emitting blocks 32 and 33.
The color of the element specifying auxiliary pattern iDm in pR1 and DpR2 is cyan. Similarly, the dot pattern for G DpG
The color of the element identification auxiliary pattern iDm is magenta,
The color of the element specifying auxiliary pattern iDm in the B dot pattern DpB is yellow.

(Details of the Second Step) In the second step, as described above, the light emission amount inspection dot pattern composed of the density inspection pattern and the auxiliary pattern is captured by the scanner 80 at one time. As shown in FIG. 11, the scanning direction at the time of capturing is along the main scanning direction when the latent image of the dot pattern for light emission amount inspection is formed by the print head. Therefore, the density inspection patterns formed by the R1, R2, G, and B exposure blocks can be captured at exactly the same time. Specifically, first, the line scanner 80
Are dot patterns DpR1, DpR2, G for R1 and R2.
The density inspection pattern and the auxiliary pattern included in each of the dot pattern DpG for dot and the dot pattern DpB for B are simultaneously captured, and the density signal obtained from each inspection unit image included in the density inspection pattern is converted into an image processing unit 82. At the same time, the above-described various information included in the auxiliary pattern is also sent to the image processing unit 82.

(Details of Third Step) In the third step, first,
The image processing unit 82 converts the linear measurement dots DLe, DL
o (ie, unit image for inspection), the second
The density value obtained by the scanning operation in the process is associated with the address in the row of the corresponding light emitting element based on information obtained from the element specifying auxiliary pattern and other auxiliary patterns. The information obtained from the auxiliary pattern is R1, R2, G
Which of the light emitting blocks B is arranged adjacently to the dot pattern (color index pattern iDC), position information in the sub-scanning direction (sub-scanning index pattern iD)
s), position information in the main scanning direction (element identification auxiliary pattern iDm), and the like. Then, the image processing unit 82
These density values are digitized into a form such as a ratio with respect to a predetermined reference value, and are indicated on the screen of the monitor 84 as the respective light amounts of the respective phosphor elements F to be inspected. In the notation method exemplified on the screen of the monitor 84 in FIG. 12, for each emission color of R1, R2, G, and B arranged on the horizontal axis, the emission amount of all the light-emitting elements on the emission block of that color is: N symbols S arranged on the vertical axis to indicate addresses in the column of each light emitting element
(In the figure, N is 1, 2, 2,
3,. . n, etc.).

[Another Embodiment] <1> In the above embodiment, RG is printed on one sheet of photographic paper.
The pattern for density inspection of each color of CMY based on the phosphor of each emission color of B is formed in a form in which three colors are aligned, but actually, the pattern for density inspection of some colors of CMY is formed according to circumstances. It is also possible to form only the pattern color, and a method for inspecting the light emission amount of a print head using the same is also within the scope of the present invention.

<2> In the above embodiment, the phosphor element is
Although it corresponds to a plurality of light emitting elements, a print head using a PLZT optical shutter array or a DMD (digital micromirror device) or the like as a plurality of light emitting elements may also be used as the light emitting amount inspection method of the present invention. Can be applied.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a print head of a fluorescent printer according to the present invention.

FIG. 2 is an enlarged plan view as viewed from an arrow II-II in FIG.

FIG. 3 is a schematic perspective view of a print head portion.

FIG. 4 is a schematic plan view showing a paper mask and a reciprocating mechanism for a print head.

FIG. 5 is a schematic side view showing a paper mask and a print head reciprocating mechanism.

FIG. 6 is a schematic block diagram showing exposure control by a print head.

FIG. 7 is a schematic plan view showing one of the light-emitting blocks.

FIG. 8 is a schematic view showing one embodiment of a dot pattern for light emission amount inspection according to the present invention.

9 is an enlarged view of a main part of FIG. 8;

FIG. 10 is an enlarged view of another main part of FIG. 8;

FIG. 11 is a schematic view showing a scanning procedure of a dot pattern for light emission amount inspection.

FIG. 12 shows an example of a light emission amount inspection result displayed on a monitor.

FIG. 13 is an explanatory view showing a conventional example of an inspection dot pattern.

[Explanation of symbols]

 Reference Signs List 60 print head 80 scanner 82 image processing section 84 monitor F phosphor element (light emitting element) Dp4 dot pattern for light emission amount inspection iDm auxiliary pattern for element identification DLe line-shaped measuring dot (even address) DLo line-shaped measuring dot (Even address) BgL Dot for line background

Claims (6)

[Claims] 1. A light-emitting device comprising: a plurality of light-emitting elements arranged in a row along a main scanning direction on a print head; A method for inspecting a light emission amount of a print head based on the density of a unit image for inspection, comprising: <1> a first step of forming a predetermined light emission amount inspection dot pattern on a photosensitive material by the print head; However, the predetermined light emission amount inspection dot pattern is a density inspection pattern obtained by gathering the inspection unit images formed by the light emitting elements, and a density inspection pattern in each density inspection pattern area. In order to specify the address information in the row of the light emitting elements on which the individual inspection unit images have been formed, elements provided adjacent to the specific inspection unit image in each of the density inspection pattern areas. <2> a second step of simultaneously capturing the density inspection pattern and the element specifying auxiliary pattern by a scanner, and <3> based on information obtained from the element specifying auxiliary pattern. A light emission amount inspection of a print head comprising a third step of associating a density read value of each inspection unit image in each of the density inspection patterns with an address in the row of the corresponding light emission element. Method. 2. The print head is provided with light emitting elements having different emission light colors in the row for each color, and the element specifying auxiliary pattern for each color is used for a density test for each color. 2. The light of the print head according to claim 1, comprising dots of the same color as the corresponding density inspection pattern formed adjacent to the inspection unit image by a part of the light emission elements formed with the pattern. Emission amount inspection method. 3. The light-emitting element on which the part-specific auxiliary pattern is formed is one light-emitting element disposed at the center in the main scanning direction on the print head. Inspection method of light emission amount of print head. 4. The plurality of light emitting elements are arranged in a row along the main scanning direction of the print head for each of the emitted light colors of RGB to constitute a line-shaped print head. 4. The method according to claim 1, wherein the light-emitting device is configured to be moved in a sub-scanning direction with respect to the photosensitive material. 5. The first step, wherein the inspection unit image and the element specifying auxiliary pattern form a plurality of dot images arranged linearly in the sub-scanning direction.
5. The method according to claim 4, wherein the method is performed while moving the print head in the sub-scanning direction. 6. The method according to claim 1, wherein the plurality of light emitting elements are phosphor elements.