JP3107576B2 - Image recording apparatus and method of adjusting image recording apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acousto-optic modulator
AOM), the intensity of light from a light source is modulated, and the modulated light is irradiated on a photosensitive material to record an image. The present invention relates to an image recording device that requires accurate recording.

[0002]

2. Description of the Related Art Since the finished density of a film differs from one developing machine to another, and the components of an exposure system also have individual differences, a serviceman of a maker appropriately sets the light amount of a light source in an image recording apparatus on site. There are the following methods for setting the light amount in this case. (1) This is a method in which the maximum value of an image signal that can take a gradation is determined from the finished print density, and the image signal is assigned to an area that does not exceed the maximum value. For example, as shown in FIG. 6, it is assumed that the light amount itself of the intensity modulated light (writing light) can be changed from 0 to 4095 in terms of a digital value.
It is assumed that the finished density curve for the input digital value has a characteristic of being saturated at 3071. In this case, 3072 ~
Even if assigned to 4095, there is no change in gradation and it does not make sense as an image. Therefore, the amount of writing light that can be used is 0 to 3071 in terms of an input digital value, and the image signal is assigned to 0 to 3071. (2) This is a method of inserting and removing an optical filter as shown in FIG. That is, an optical filter is developed and developed, and the density is measured. If the density is appropriate, the density is kept as it is. If the density is inappropriate, another filter is inserted and the exposure, development, and judgment are performed again to determine the optimal density. This is continued until a suitable concentration is obtained. (3) This is a method in which the gain of the AOM is changed to cope with the change.
Since the characteristics of the AOM change as shown in FIG. 8, the exposure efficiency is changed by changing the diffraction efficiency (primary light / incident light) so as to adjust to the optimum density. Note that it is common to use primary light as writing light. (4) This is a method for reducing the input signal to the AOM.

[0003]

The above-mentioned method (1) has a problem that the dynamic range of the image signal is narrowed and the quality of the image is reduced. For example, in the case of 12 bits, information of 4095 steps can be reproduced if it can be used in the entire range. However, when the characteristics of the film are steep as shown in FIG.
The data of 72 to 4095 steps will be discarded,
There is a problem that the density step width of the reproduced image becomes coarse and the image quality deteriorates. The method (2) is troublesome, and exposure, development, and density measurement may be repeated many times. In this case, there is a problem that the film is wasted and it is necessary to prepare various kinds of optical filters. In the method (3), as shown in FIG. 10, even if the input signal is zero, the AOM is a first-order light called a leak light (a diffracted light shown in FIG. 9).
Weak light exists. Therefore, when the AOM is used with a low gain, the dynamic range (maximum light amount / minimum light amount) of the writing light is reduced. As a result, there is a problem that fogging occurs in the film. The method of (4) has the same problem as the method of (3), and if the dynamic range of the input signal is reduced, S / S
N deteriorates, resulting in a decrease in image quality.

[0004] The present invention avoids such a problem and provides a modification.
It is an object of the present invention to provide an image recording apparatus and an image recording apparatus adjustment method which can fully utilize the dynamic range of the adjusting means and the light source, are easy to realize, and can simplify the adjustment operation of the apparatus.

[0005]

An image recording apparatus according to the present invention uses a variable light source as a light source and generates a test pattern signal having a plurality of signal levels including a maximum value of an image signal. Before adjusting the light emission amount of the light source
A light amount adjusting means for setting a new maximum light amount of the light source .

In the method of adjusting an image recording apparatus according to the present invention, the maximum light amount of the light source is set based on the density value of the developed test pattern.

[0007]

[Action] First, while setting the maximum light amount of the current source, the exposure test pattern of the signal level of the test pattern and the maximum value <br/> peripheral corresponding to the maximum value of the image signal, and developed the
The density value of the test pattern is determined, and the upper limit of the density value of the image to be reproduced is determined. Then, the light emission amount of the light source corresponding to the upper limit value is set to a new maximum light amount (maximum light amount of the light source).
It shall be the value). The range where the light emission amount of the light source is 0 to the maximum value is an area where the print density changes according to the change in the light amount.
Origination amount of to a maximum value, order to effectively use the resolution has a like modulation means (AOM), is gradation in accordance with all the steps of the image signal (i.e., the input range of the image signal
Was corresponding to the light emission amount of 0 to a maximum value), we reproduce a fine image by effectively utilizing the dynamic range of such modulation means.
In addition, when the serviceman sets the light emission amount of the light source in the field, the work is completed by one exposure and development of the test pattern and the subsequent setting of the maximum light amount of the light source, so that the adjustment work of the apparatus is simplified. You.

[0008]

Next, an embodiment of the present invention will be described with reference to the drawings.

Embodiment 1 (FIGS. 1, 2, and 3) An adjustment method of an image recording apparatus will be described with reference to FIG. First, the pattern for maximum density adjustment is exposed (step 10) and developed (step 11). If the image signal has a depth of 10 bits,
The illustrated pattern A corresponds to the input digital value 1023,
Pattern B is 900, C is 800, D is 700, E is 60
0 and F correspond to 500 respectively. In the present embodiment, the pattern A is the pattern 30 corresponding to the maximum value of the image signal. Next, the density of each pattern is measured (step 12), and the change in density with respect to the input signal value is graphed (step 13).

Next, the input signal value corresponding to the required maximum density value is determined (step 14). In the present embodiment, the upper limit of the region where the density changes substantially linearly, that is, C is selected as the upper limit of the input signal. Next, the maximum light amount of a light source such as a laser is set to a value corresponding to the selected upper limit (step 15). If the image signal is 10 bits as described above
If the maximum light intensity of the light source corresponds to the input digital value 1023,
You.

FIGS. 2 and 3 show examples of selecting the upper limit value of the input signal.
Some explanations will be made with reference to FIG. For example, if the print density is 3.
If it is determined that it is sufficient to reproduce the data to 0, the maximum emitted light amount of the laser is adjusted so as to become A in FIG. When the density is required up to 3.2, B in FIG. 2 may be set as the maximum value of the exposure amount. Also, the state of the automatic processor (model,
Depending on the development temperature, the characteristics may change as shown in FIGS. In the case of a characteristic such as a, the maximum light amount may be set to C. In the case of b, the maximum light amount may be D.

Embodiment 2 (FIGS. 4 and 5) FIG. 4 shows an example of an apparatus configuration for implementing the method of Embodiment 1. This image recording apparatus includes a medical image data memory 20, a test pattern memory 21, a signal correction circuit (LUT) 22, a D / D
A conversion circuit 23, AOM driver 24, AOM 25, 1
Slit 26 for separating the next / zero-order light and polygon mirror 27
Lens 28, photosensitive film 29, input means 32
, A CPU 33, an APC (automatic power control) circuit 34,
And a laser (LD) 35.

The operation of this device will be described with reference to FIG.
First, the CPU 33 sets a light amount setting signal so that the light amount becomes maximum (step 40), and modulates the intensity of the laser light while supplying the test pattern output from the test pattern memory 21 to the D / A conversion circuit 23. The test pattern is recorded (step 41). Subsequently, development and exposure are performed, and the operator determines the density value and determines the maximum density (step 4).
2). Next, a desired light amount set value is input from the input means 32 (step 43). Then, CPU 33 sends out a light amount setting signal to the APC circuit 34 so that the input setting value, most large light amount of the laser 35 is set (step 44).
This ends the adjustment.

Also, the determination of the density value of the test pattern can be performed by using the automatic reading device 31 without relying on the operator, and the read data can be directly sent to the CPU 33 to let the CPU 33 make the determination. This makes it possible to completely automate the operation of setting the maximum light amount of the light source.

The number of test patterns is preferably larger as the number of test patterns can be set more finely. However, with at least 16 patterns, almost satisfactory adjustment is possible.

[0016]

As described above, according to the present invention, the following effects can be obtained. (1) Modulation means (AOM, etc.) and the dynamic range of the photosensitive film and all of the image information can be used effectively,
Reproduces fine grayscale images. (2) When the serviceman performs adjustment of the apparatus on site, the test pattern can be exposed and developed only once, thereby simplifying the operation.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a procedure for setting a maximum light amount.

FIG. 2 is a diagram illustrating an example of a change in a density value on a photosensitive film with respect to an input signal.

FIG. 3 is a diagram showing another example of a change in density value on a photosensitive film with respect to an input signal.

FIG. 4 is a diagram illustrating an example of a configuration of an image recording apparatus to which the present invention has been applied.

FIG. 5 is a flowchart showing an operation procedure of the apparatus of FIG.

FIG. 6 is a diagram illustrating a relationship between an input digital value and a finished density for explaining a conventional example.

FIG. 7 is a diagram showing a main part configuration of another conventional example.

FIG. 8 is a diagram for explaining still another conventional example.

FIG. 9 is a diagram for explaining another conventional example.

FIG. 10 is a diagram for explaining a problem of the conventional example of FIG. 9;

[Explanation of symbols]

 20 Medical image data memory 21 Test pattern memory 22 Signal correction circuit (LUT) 23 D / A conversion circuit 24 AOM driver 25 AOM 26 Primary / 0th order light separation pinhole 27 Polygon mirror 28 Fθ lens 29 Photosensitive film 30 Test Pattern 31 Automatic reading device 32 Input means 33 CPU 34 APC (automatic power control) circuit 35 Laser chip

Claims (3)

(57) [Claims] A light source capable of changing a light emission amount; and a modulating means for modulating the intensity of light from the light source. The modulating means includes an image signal having information of an image to be recorded. Is supplied as a modulation signal, and an intensity-modulated light is irradiated on a photosensitive material to record an image. The image recording apparatus generates a test pattern signal having a plurality of signal levels including a maximum value of the image signal. Test pattern signal generating means for adjusting the light emission amount of the light source to obtain a new maximum light amount of the light source.
An image recording apparatus comprising: a light emission amount adjusting unit for setting . 2. The method according to claim 1, wherein the test pattern signal is transformed as a modulation signal.
Recorded on the photosensitive material by the intensity modulating the light from the light source while supplying the regulating means has a concentration reading means for reading the density of a test pattern consisting of a plurality of patterns different concentrations, light emission amount adjustment means, from the density value of read written test patterns to determine the maximum density value to be reproduced, the outgoing light intensity of the light source to provide the density value is set as a new maximum amount <br/> of the light source The image recording apparatus according to claim 1, wherein: 3. An adjusting method of an image recording apparatus for recording an image by modulating the intensity of light from a light source capable of changing a light emission amount by a modulating means and irradiating the modulated light to a photosensitive material. First, a test pattern signal having a plurality of signal levels including the maximum value of the image signal is generated, a test pattern corresponding to the signal is recorded on a photosensitive material, and the density of the recorded test pattern is determined. determined, then, to determine the upper limit of the reproduction want density value, and sets the outgoing <br/> light quantity of the light sources corresponding to the upper limit of the determined density value as a new maximum amount of the light source Adjustment method for image recording device.