JPH07212530A - Picture output device - Google Patents

Abstract

PURPOSE:To provide a picture output device which can precisely adjust light quantity to photosensitive material whose sensitivity considerably differs by switching and selecting a conversion gain at the time of converting light quantity with which the photosensitive material is irradiated into a voltage value. CONSTITUTION:Light quantity of exposed light, which is adjusted to be appropriate by the light quantity adjustment filter of an exposure head, is converted into the voltage value by a photoelectric conversion means constituted by a light quantity sensor 41 and a C/V converter 42. At that time, a switch SW1 is operated and one of feedback resistances 44 and 45 is connected to the C/V converter 42 so as to switch the conversion gain. Thus, light quantity of the photosensitive material whose light quantity adjustment width considerably differs such as different photosensitive material can be converted into the voltage value by the appropriate conversion gain with such constitution. Thus, light quantity in the middle of adjustment can precisely be identified to various photosensitive materials, and light quantity by the light quantity adjustment filter can precisely be adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an image output for recording an image on a photosensitive material by emitting exposure light from an exposure head in accordance with image information (exposure pattern) from an image input device, an image data storage device or the like. The present invention relates to an apparatus, and more particularly to a technique for switching and adjusting the amount of exposure light applied to a photosensitive material to an appropriate amount of light according to the sensitivity of the photosensitive material.

[0002]

2. Description of the Related Art An image output apparatus of this kind is provided with, for example, a rotary drum on which a photosensitive material is mounted, and an exposure head movable in the axial direction of the rotary drum. The exposure head is configured to be capable of emitting a plurality of laser beams (exposure beams), and these laser beams are turned ON / O according to the exposure pattern.
The laser light turned on and turned on exposes the photosensitive material. Then, the rotary drum is rotated to displace the positional relationship between the exposure head and the photosensitive material in the main scanning direction to perform exposure in the main scanning direction, and the exposure head is moved in the axial direction of the rotary drum to expose the exposure head. Exposure in the sub-scanning direction is performed by displacing the positional relationship of the photosensitive material in the sub-scanning direction.

The exposure (image recording) on the photosensitive material is
Since it is necessary to expose the photosensitive material with an appropriate amount of light, the exposure head is provided with a light amount adjustment filter for adjusting the amount of laser light.

By the way, since the sensitivities of the light-sensitive materials differ from one manufacturer to another, it is necessary to change the light quantity at the time of exposure according to the sensitivity of the light-sensitive materials. Therefore, the light amount adjusting filter of the conventional device is, for example, a variable ND (Neutral Density).
) A filter, two deflection filters, etc. are provided so that the light amount can be continuously switched and adjusted.

In the variable ND filter, as shown in FIG. 19A, a plurality of types of ND filters are coated in the circumferential direction so that the attenuation rate of the laser beam LB changes continuously. By driving the motor 101 to rotate the variable ND filter 100 and switching the ND filter through which the laser light LB passes, the attenuation rate of the laser light LB continuously changes, and the output light from the variable ND filter 100 is changed. The light quantity of the OLB is continuously switched and adjusted. In addition,
In the figure, reference numeral 102 has the lowest attenuation rate (the maximum output light amount)
The reference numeral 103 designates an ND filter, and the reference numeral 103 designates an ND filter having the highest attenuation rate (the minimum output light amount). Each ND filter that constitutes the variable ND filter 100 is the ND filter 10
2 to the ND filter 103 are arranged so that the attenuation rate gradually increases.

A light quantity adjusting filter constructed by using two deflection filters is constructed by rotating the deflection filter 112 with respect to the deflection filter 111 by a motor 113 as shown in FIG. 19B. By changing the angle of the deflection surface of the laser light from each deflection filter continuously from 0 ° to 90 °, the deflection filter 11
The light extinction ratio of the laser beam OLB output from 2 is continuously changed, and the output light amount is continuously switched and adjusted.

Further, some conventional apparatuses are equipped with a light quantity detecting mechanism for detecting the quantity of light emitted from the exposure head onto the photosensitive material and converting the detected quantity of light into an electric signal for output.

For example, when the sensitivity of the photosensitive material, that is, the appropriate light amount is changed, such as when the image recording process for the photosensitive material of a certain manufacturer is changed to the image recording process for the photosensitive material of a different manufacturer, the light amount detecting mechanism outputs the light. The adjustment amount of the light amount adjustment filter is changed (the motor 101 is driven in the case of FIG. 19A or the motor 113 is driven in the case of FIG. 19B) according to the level of the electric signal to be generated. Is configured.

[0009]

However, the conventional example having such a structure has the following problems. The photosensitive material used in this type of image output device is
For example, there are a plurality of types of light-sensitive materials, such as a high-sensitivity type such as a silver salt film and a low-sensitivity type such as a printing plate. And, as described above, the sensitivity of each type of photosensitive material differs depending on the manufacturer of the photosensitive material. FIG. 20 shows the relationship between each type of photosensitive material and the appropriate amount of light of each photosensitive material.

By the way, in the conventional apparatus, the apparatus is constructed so that an image can be recorded on the same type of photosensitive material. That is, for example, in a high-sensitivity image output device for a photosensitive material, the light amount adjustment filter can adjust the light amount within an appropriate light amount width (TK _{1 to} TK ₂ ) for each manufacturer.

Therefore, when an image is recorded on a photosensitive material having a remarkably different sensitivity (appropriate light quantity), such as a photosensitive material of a kind different from the kind of the photosensitive material to be processed by the conventional apparatus, first, the light quantity is adjusted. It is necessary to change the light amount adjustment range of the filter for each type of photosensitive material.
For example, the variable ND filter (see FIG. 19 (a)) is divided into two regions, and in one region, the light amount adjustment (TK _{1 to} TK ₂ ) for the highly sensitive photosensitive material is continuously performed. In the other region, it is possible to cope with the problem by using a light quantity adjusting filter configured to continuously perform the light quantity (TK _{3 to} TK ₄ ) of the low-sensitivity photosensitive material.

However, in such a case, there are the following problems.

For example, in an apparatus constructed by processing a high-sensitivity light-sensitive material (silver salt film or the like) as shown in FIG.
As shown in (a), the conversion gain is adjusted to be relatively large so that the change in the light amount in the low range can be accurately identified. The light amounts TK ₁ and TK ₂ in the figure have the same light amount shown in FIG. Therefore, if an image is recorded on a low-sensitivity light-sensitive material (a printing plate, etc.) with this apparatus, the above TK ₂
Much higher light intensity T _{3 to} TK ₄ (see FIG. 20)
And it must be converted into an electrical signal by the conversion gain, as shown in FIG. 21 (b), and immediately saturated (over range), in the figure, identify the change in the amount of light in the TK ₅ ~TK ₄ Therefore, there is a problem in that the light amount adjustment by the light amount adjustment filter cannot be properly performed.

On the contrary, in an apparatus constructed by processing a low-sensitivity photosensitive material, as shown in FIG. 21 (c), it is possible to accurately discriminate light quantity changes in a high range without over-ranging. The conversion gain is adjusted to be relatively small. Therefore, when an image is recorded on a high-sensitivity light-sensitive material with this device, the light amount T _{1 to} TK ₂ (see FIG. 20), which is much smaller than the above TK ₃ , is converted into an electric signal with the above conversion gain. 21 (d), the inclination of the change of the electric signal with respect to the change of the light amount becomes small, so that the change of the light amount (for example, TK _{6 to} TK).
₇ ) changes in the level of the electric signal (SD _{1 to} S
There is a problem that D ₂ ) becomes difficult to identify.

Further, for example, in the case where the electric signal output from the light amount detecting mechanism is converted into digital data and the light amount is adjusted by the light amount adjusting filter by a microcomputer or the like, as shown in FIG. 21 (d). When
Since the light quantity width corresponding to digital data becomes large,
There is also a problem that the microcomputer cannot accurately identify the change in the light amount, and as a result, the light amount adjustment filter cannot accurately adjust the light amount.

The present invention has been made in view of the above circumstances, and provides an image output device capable of accurately adjusting the light amount of a photosensitive material having significantly different sensitivity (appropriate light amount) such as between different photosensitive materials. With the goal.

[0017]

The present invention has the following constitution in order to achieve such an object. That is, the invention according to claim 1 is an image output device for recording an image on a photosensitive material by emitting exposure light from an exposure head in accordance with an exposure pattern, and a light amount for adjusting the light amount of the exposure light applied to the photosensitive material. An adjustment filter, a light amount adjustment switching unit that switches the light amount adjustment amount of the light amount adjustment filter, and a light amount of the exposure light adjusted by the light amount adjustment filter and applied to the photosensitive material is detected, and the detected exposure A photoelectric conversion unit that outputs a voltage according to the amount of light,
Gain switching means for switching the conversion gain of the photoelectric conversion means.

According to a second aspect of the present invention, in the image output apparatus according to the first aspect, the A / D conversion for converting the voltage value (analog data) converted by the photoelectric conversion means into digital data. Means, setting means for setting the sensitivity of the photosensitive material, and according to the sensitivity of the photosensitive material,
Based on the digital data converted by the A / D conversion means and the gain switching control means for controlling the switching of the conversion gain of the gain switching means, the light amount of the exposure light with which the photosensitive material is irradiated is changed to that of the photosensitive material. Light quantity adjustment switching control means for controlling switching of the light quantity adjustment switching means so as to adjust to an appropriate light quantity according to sensitivity.

[0019]

The operation of the invention described in claim 1 is as follows. The light quantity of the exposure light adjusted by the light quantity adjusting filter and applied to the photosensitive material is converted into a voltage value by the photoelectric conversion means. At this time, the conversion gain of the photoelectric conversion means is selected by the gain switching means according to the sensitivity of the photosensitive material to be processed. Then, in accordance with the voltage value converted by the photoelectric conversion means, the light quantity adjustment switching means adjusts the light quantity of the exposure light applied to the photosensitive material to an appropriate light quantity according to the sensitivity of the photosensitive material to be processed. The light amount adjustment amount of the adjustment filter is switched and adjusted.

In the invention according to claim 2, the voltage value converted by the photoelectric conversion means is converted into digital data,
The light quantity adjustment amount of the light quantity adjustment filter is automatically adjusted on the basis of the digital data, and its operation is as follows.

The voltage value (analog data) converted by the photoelectric conversion means is converted into digital data by the A / D conversion means and given to the light amount adjustment switching control means. The conversion gain of the photoelectric conversion means at this time is switched by the gain switching control means according to the sensitivity of the photosensitive material set by the setting means. Then, the light quantity adjustment switching control means switches the light quantity adjustment switching means so as to adjust the light quantity of the exposure light applied to the photosensitive material to an appropriate light quantity according to the sensitivity of the photosensitive material based on the given digital data. To control.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing the configuration of an image output apparatus according to the first embodiment of the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a diagram showing the internal configuration of an exposure head of the first embodiment. FIG.

The apparatus of the first embodiment is constructed so that it can be used for both image recording on a high-sensitivity light-sensitive material (for example, a silver salt film) and a low-sensitivity light-sensitive material (for example, a printing plate). . The first embodiment device is also configured to manually adjust the light amount. Further, the first embodiment device (image output device) constitutes a part of an image recording system (hereinafter, simply referred to as “system”) including an image input device (or image data recording device), a photosensitive material supply device, and the like. It is a device that does. That is, the image recording processing information such as the image information (exposure pattern) read by the image input device or the like is supplied from the system to the first embodiment device.

In the figure, reference numeral 1 indicates a rotary drum. The photosensitive material F supplied from a photosensitive material supply device (not shown) is adsorbed and held on the peripheral surface of the rotary drum 1, and an image is recorded on the photosensitive material F. The rotating drum 1 is rotated in the circumferential direction of the rotating drum 1 by a motor 2.

An exposure head 3 is arranged close to the rotary drum 1. The exposure head 3 is screwed onto a screw shaft 4 arranged in the axial direction of the rotary drum 1 and guided by a guide shaft 5 arranged parallel to the screw shaft 4.
When the screw shaft 4 is rotated by the motor 6, the exposure head 3 is moved in the axial direction of the rotary drum 1. That is, when the image is recorded on the photosensitive material F, the exposure head 3 is moved in the axial direction of the rotary drum 1 so that the exposure head 3 is sub-scanned and fed to the photosensitive material F adsorbed and held on the peripheral surface of the rotary drum 1. It Also, the rotating drum 1
The main scanning feed of the photosensitive material F to the exposure head 3 is performed by rotating the photosensitive material F in the circumferential direction.

Next, the internal structure of the exposure head 3 will be described with reference to FIG. As will be described later, the gas laser 1
The laser light emitted from the beam splitter 1 is
However, since the drawing is complicated, only the optical axis is drawn in FIG.

A gas laser (for example, an argon laser) 11 is attached to the exposure head 3 so that the emission direction of the laser light is parallel to the axis of the rotary drum 1. The laser light emitted from the gas laser 11 is split into a plurality of (for example, 10) laser lights by the beam splitter 12 and is incident on the acousto-optic modulator (AOM) 13. The AOM 13 independently modulates (ON / OFF) each laser beam incident from the beam splitter 12 according to the exposure pattern. In addition,
The ON / OFF control unit 13a controls ON / OFF of each laser beam by the AOM 13 according to an exposure pattern supplied from a system (not shown).

The respective laser beams emitted from the AOM 13 have their optical paths folded back by the mirrors 14 and 15 in a direction parallel to the laser beam emission direction (the right direction in FIG. 3) and the opposite direction (the left direction in FIG. 3). It is incident on the reduction lens system 16. Each laser beam emitted from the first reduction lens system 16 enters a light amount adjusting filter 17, is adjusted to an appropriate light amount according to the sensitivity of the photosensitive material F adsorbed and held on the rotating drum 1, and then the zoom lens. It is incident on 18. Zoom lens 1
Each laser beam emitted from 8 passes through a lens 19 which constitutes a second reduction lens system, and has an optical path of 90 ° at a mirror 20.
After being folded back, an image is formed on each exposure dot of the photosensitive material F adsorbed and held on the rotary drum 1 through the imaging lens 21 forming the second reduction lens system. A shutter 22 driven by a rotary solenoid 23 is provided between the mirror 20 and the imaging lens 21 to prevent exposure fog on the photosensitive material during standby. In addition, the first reduction lens system 16, the zoom lens 18, and the second reduction lens system (lens 19 and imaging lens 21) have a distance (for example, 15 mm) between the laser beams split by the beam splitter 12, Exposure dot spacing (eg 5.7μ
m) and the zoom lens 18 adjusts the exposure dot interval to an arbitrary value. Further, a light amount detecting mechanism, which is an essential part of the present invention, for detecting the light amount of the laser light with which the light amount adjusting filter 17 adjusts the light amount and is applied to the photosensitive material F is provided near the shutter 22. This configuration will be described later.

Next, the structure of the light quantity adjusting filter 17 will be described with reference to FIGS. FIG. 4 is a diagram showing a configuration of a light amount adjustment filter of the first embodiment device, and FIG.
It is a figure for demonstrating the light amount adjustment by the light amount adjustment filter.

As shown in FIG. 4, the light amount adjusting filter 17 comprises a coarse adjusting ND filter 31 and a fine adjusting ND filter 32. The fine adjustment ND filter 32 has the same configuration as the variable ND filter described with reference to FIG. 19A, and as shown in FIG. 5A and FIG. The output light quantity is set to TK _{3 to} T so that the light quantity of the photosensitive material F can be adjusted.
A plurality of types of ND filters adjusted to K ₄ are coated in the circumferential direction. Fine adjustment N by driving the motor 33
By rotating the D filter 32, the light amount of the output laser light OLB is finely adjusted according to the fluctuation of the appropriate light amount for each manufacturer of the same type of photosensitive material F.

The coarse adjustment ND filter 31 is shown in FIG.
As shown in (a), the laser light LB is attenuated by (TK ₃ −TK ₁ ), that is, the attenuation rate is {(TK ₃ −
TK ₁ ) / TK ₃ }.

When exposing the low-sensitivity (high appropriate light amount) photosensitive material F, the rotary solidoid 34
Is driven to retract the coarse adjustment ND filter 31 from the optical path of the laser beam LB as shown by the solid line in FIG. In the adjustment ND filter 21, the ND filter having the highest attenuation rate is arranged on the optical path).
The rotation is performed between θ _E ° (a state in which the ND filter having the lowest attenuation rate in the fine adjustment ND filter 21 is arranged on the optical path). On the other hand, when exposing the photosensitive material F having high sensitivity (low proper light amount), the rotary solidoid 34 is driven to drive the coarse adjustment ND filter 31 to the laser beam LB as shown by the chain double-dashed line in FIG. By arranging on the optical path, the amount of light is adjusted by rotating the fine adjustment ND filter 31 between 0 ° and θ _S1 ° with respect to the laser beam LB ′ attenuated by the coarse adjustment ND filter 32. Be done. In the figure, TK ₁ , TK ₂ , TK ₃ , TK ₄
Is the same as the light amount shown in FIG.

When the highly sensitive photosensitive material F is exposed, the fine adjustment ND filter 3 is applied to the laser light LB 'whose output light amount is attenuated by the coarse adjustment ND filter 31.
It is only necessary to make fine adjustments in step 2, so the ND filter for coarse adjustment 3
The attenuation rate of 1 is {(TK ₃ −TK ₁ ) / TK ₃ } or more,
It may be equal to or less than {(TK ₄ −TK ₂ ) / TK ₄ }. For example, as shown in FIG. 5B, when the attenuation rate of the coarse adjustment ND filter 31 is set to {(TK ₄ −TK ₂ ) / TK ₄ }, the fine adjustment ND filter 32 is set to θ _S2 °. ~ Θ _E °
The light amount of the highly sensitive photosensitive material F is adjusted by rotating the photosensitive material F between them.

Although only one laser beam is drawn in FIG. 4, the plurality of laser beams split by the beam splitter 12 all pass through the ND filter having the same attenuation rate of the fine adjustment ND filter 31. .

On the contrary, if the sensitivity of the photosensitive material F, which has a high sensitivity variation among manufacturers, is large, that is, the inequality {(TK ₄ -TK ₃ ) / TK ₄ } <{(TK ₂ -T
When K ₁ ) / TK ₂ } is satisfied, the light amount adjustment by the fine adjustment ND filter 32 may be performed so that the light amount adjustment (TK _{1 to} TK ₂ ) of the photosensitive material F with high sensitivity can be performed.

By the way, in this embodiment, the motor 33 is
The rotation drive and the drive of the rotary solenoid 34 are configured to be manually performed by the operator from the operation switch 35 based on the data detected by the light amount detection mechanism described later and displayed on the display device.

The lamps 36 and 37 are NDs for coarse adjustment.
This is for notifying the operator of the states of the filter 31 and the fine adjustment filter 32. That is, when the coarse adjustment ND filter 31 is arranged on the optical path, the limit switch 3
The lever 38a of 8 is pushed down and the lamp 36 lights up,
In addition, N that has the highest attenuation rate of the fine adjustment ND filter 32.
When the D filter is arranged on the optical path (the rotation angle is 0 °), the lever 39a of the limit switch 39 is pushed down and the lamp 37 is turned on.

The light amount adjusting filter 17 corresponds to the light amount adjusting filter in the present invention, and is the motor 33.
The rotary solenoid 34 and the rotary solenoid 34 correspond to the light amount adjustment switching means in the present invention.

Further, as shown in FIG. 6, an ND filter 31a having the same structure as the coarse adjustment ND filter 31 is provided, and the ND filter 31a and the fine adjustment ND filter 32 are used to remove the photosensitive material F of each type. The light amount may be adjusted. In this case, the attenuation rate of the ND filter 31a is {TK ₄ −√ (TK ₃ × TK ₄ )} / TK ₄ . With this configuration, it is possible to perform finer light amount adjustment. It is needless to say that two or more ND filters 31a may be provided, and the ND filters 31a and the fine adjustment ND filter 32 may be used to adjust the light amount of each type of photosensitive material F.

Next, the structure of the light amount detecting mechanism provided in the apparatus of this embodiment will be described with reference to FIGS. 7 and 8. Figure 7
FIG. 8 is a diagram showing a configuration of a light amount detection mechanism, and FIG. 8 is a diagram showing a circuit configuration thereof.

As shown in FIG. 7, a light amount sensor 41 such as a solar cell is attached to the inner surface of the shutter 22 which is opened and closed by the rotary solenoid 23. When the shutter 22 is closed, the light amount sensor 41 is located on the optical path of the laser light. The light quantity sensor 41 outputs a current value proportional to the quantity of incident laser light. As shown in FIGS. 7 and 8, the output current I is input to a C / V converter (current / voltage converter) 42, converted into a voltage value and output, and based on the voltage value, a light amount sensor Data indicating the amount of light incident on 41 is displayed on the display device 43.

Further, in this embodiment, the C / V converter 4 is used.
Two feedback resistors 2 are connected to each other. These feedback resistors 44 and 45 are the switches SW1 depending on the type (sensitivity) of the photosensitive material F to be processed.
Either one is configured to be selectively switchable.
The switching operation of the switch SW1 is manually performed by an operator.

The feedback resistor 44 has a large resistance value R1 so that the adjusted light amount for the highly sensitive photosensitive material F can be detected accurately, while the feedback resistor 45 is provided.
Has a small resistance value R2 so that the adjustment light amount for the low-sensitivity photosensitive material F can be accurately detected without exceeding the conversion range of the C / V converter 42.

That is, the feedback resistor 44 is C /
The relationship between the current I and the output voltage V when connected to the V converter 42 is as shown in the following equation. V = R1 × I

The relationship between the current I and the output voltage V when the feedback resistor 45 is connected to the C / V converter 42 is as shown in the following equation. V = R2 × I

The light quantity sensor 41 and the C / V converter 42 correspond to the photoelectric conversion means in the present invention. Also, switching the resistance value corresponding to the conversion gain, that is,
A plurality of feedback resistors 44 and 45 (two in this embodiment) according to the number of types of the photosensitive material F are used for the C / V converter 4.
The configuration in which the feedback switch resistors 44 and 45 are connected to No. 2 and are switched and selected by the switch SW1 corresponds to the gain switching means in the present invention.

Next, the operation of the operator and the operation of the apparatus according to this embodiment will be described. The light amount adjustment work using the light amount detection mechanism and the light amount adjustment filter 17 is performed in the following cases.

(1) Before processing a photosensitive material F of a different type from the photosensitive material F currently being processed. (2) Before processing the photosensitive material F of the same type as the photosensitive material F currently being processed but having different sensitivity (appropriate light amount).

First, the operation of the operator in the case of (1) and the operation of the embodiment apparatus accompanying it will be described below. The worker
The switch SW1 is operated to connect either one of the feedback resistors 44 and 45 to the C / V converter 42 according to the type of the photosensitive material F to be newly processed (high sensitivity or low sensitivity). .

Next, the operator operates the operation switch 35 to change the rough adjustment N according to the type of the photosensitive material F to be newly processed.
It is operated whether or not the D filter 31 is arranged on the optical path.
At this time, the operator can know the current state of the rough adjustment ND filter 31 depending on whether or not the lamp 36 is turned on.

Next, the operator operates an operation switch (not shown) to drive the rotary solenoid 23, close the shutter 22, arrange the light quantity sensor 41 on the optical path, and split the light by the beam splitter 12. The ON / OFF control unit 13a is controlled to turn on only one of the laser lights incident on the light amount sensor 41 and turn off all the other nine laser lights.

As a result, the light amount of one laser beam with which the photosensitive material F is irradiated is detected, and the data indicating the detected light amount is displayed on the display device 43. At this time, since the feedback resistors 44 and 45 are switched to the ones according to the type of the photosensitive material F, the feedback resistors 44 and 45 are not overranged, and the change in the light amount can be accurately identified.

While observing the data displayed on the display device 43, the operator rotates the fine adjustment ND filter 32 from the operation switch 35 while the light amount detected by the light amount sensor 41, in other words, the light amount. The light amount of the laser beam applied to the photosensitive material F is adjusted to the optimum light amount of the photosensitive material F.

Next, the operation of the operator in the case of the above (2) and the operation of the embodiment apparatus accompanying it will be described below. At this time, the connection state of the feedback resistors 44 and 45 to the C / V converter 42 and the state of the coarse adjustment ND filter 31 (whether it is arranged on the optical path or retracted) remain as they are. Since it is good, the operator does not operate these.

Then, the shutter 22 is closed and the light amount sensor 41 is turned on / off so that only one laser beam is incident.
While making an instruction to the OFF control unit 13a and observing the data displayed on the display device 43, a fine adjustment is made from the operation switch 35 so as to adjust to an appropriate light amount according to the sensitivity of the photosensitive material F to be newly processed. The light amount adjustment by the ND filter 32 is operated.

As described above, the conversion range of the light amount detecting mechanism when adjusting the light amount can be switched and selected according to the type (sensitivity) of the photosensitive material F to be processed, so that different types of photosensitive materials (remarkably sensitive ones) can be selected. Even when both are used for image recording of different light-sensitive materials, optimum C / V conversion can be performed, and the light amount adjustment by the light amount adjustment filter can be performed accurately.

In the above-mentioned first embodiment and the following second embodiment, the apparatus is constructed so that it can be used for two kinds of photosensitive materials F, but more than that kind of photosensitive materials F, for example, FIG. As shown in, the device can be configured so that it can be used for image recording processing of three types of photosensitive materials F.
At this time, the light quantity adjusting filter 17 may be configured as shown in FIG. 10, and the light quantity detecting mechanism may be configured as shown in FIG.

The light quantity adjusting filter 17 shown in FIG.
The light amount adjustment filter 17 shown in FIG. 4 is provided with a rough adjustment ND filter 31b for adjusting the light amount of a medium-sensitivity photosensitive material. For the low-sensitivity photosensitive material F, the light amount is adjusted only by the fine adjustment ND filter 32, and for the high-sensitive photosensitive material F, the fine adjustment is performed on the laser light attenuated by the coarse adjustment ND filter 31. The light amount is adjusted by the ND filter 32 for adjustment, and for the medium-sensitivity photosensitive material F, the light amount is adjusted by the ND filter 32 for fine adjustment with respect to the laser light attenuated by the ND filter 31b for coarse adjustment. To be done.

Incidentally, the attenuation amount of the coarse adjustment filters 31 and 31b is adjusted. For the medium-sensitivity photosensitive material F, the fine adjustment ND filter 32 is applied to the laser light attenuated by the coarse adjustment ND filter 31b. For the highly sensitive photosensitive material F which is adjusted in the light amount, the fine adjustment ND is applied to the laser light attenuated by the coarse adjustment ND filters 31 and 31b.
The filter 32 may be configured to adjust the amount of light.

As for the light quantity adjusting filter 17, as described with reference to FIG. 6, an ND filter 31a used for fine adjustment of the light quantity of each type of photosensitive material F may be provided.

Next, in the light amount detecting mechanism shown in FIG. 11, C
/ V converter 42 has three types of feedback resistors 44
(Resistance value R1), 45 (resistance value R2), 46 (resistance value R
3) is connected, and the C / V converter 42 is connected by the switch SW1.
In this configuration, the feedback resistor connected to is switched and selected. The resistance value R3 of the feedback resistor 46 is
The size is set so that the amount of light with respect to the medium-sensitivity photosensitive material F can be accurately detected.

For use in processing four or more types of photosensitive materials F, the light quantity adjusting filter 17 may be provided with a new rough adjusting filter, etc., as described above. The light amount detection mechanism may be handled by connecting feedback resistors to the C / V converter 42 according to the type of the photosensitive material F to be processed, and switching and selecting these resistors with the switch SW1.

Next, the configuration of the second embodiment device of the present invention will be described. This second embodiment device corresponds to the invention according to claim 2, and in the above first embodiment device,
An A / D converter as A / D conversion means for converting the voltage value output from the light quantity detection mechanism into digital data, and a control section for automatically adjusting the light quantity of the light quantity adjustment filter 17 based on the digital data. Is provided.

The connection state of the control unit, the light amount adjusting filter 17, the light amount detecting mechanism and the like will be described with reference to the block diagram of FIG.

The control unit 50 is composed of a gain switching control unit 51 as a gain switching control unit and a light amount adjustment switching control unit 52 as a light amount adjustment switching control unit.

When the type 70 of the photosensitive material F is notified from the system 70 corresponding to the setting means of the present invention, the gain switching control section 51 changes the feedback resistance suitable for the notified type of the photosensitive material F to the C / V converter. The switch SW1 of the light amount detection mechanism is controlled to be connected to the switch 42. Then, the rotary solenoid 23 is driven to close the shutter 22, the light amount sensor 41 is arranged on the optical path of the laser beam, and only one laser beam is emitted from the light amount sensor 41.
The ON / OFF control unit 13a is controlled so that it is incident on. When these processes are completed, the light amount adjustment switching control unit 5
Pass control to 2.

When the control is passed, the light quantity adjustment switching control section 52 first drives the rotary solenoid 34 in accordance with the type of the photosensitive material F supplied from the system 70 to turn on the rough adjustment ND filter 31. Put it on the street,
Control whether to save. At this time, C of the light amount detection mechanism
The voltage value output from the A / V converter 42 according to the amount of light received by the light amount sensor 41 is the A / D converter 53.
Have been converted to digital data. The light quantity adjustment switching control unit 52 uses this digital data and the system 70.
The appropriate light amount corresponding to the sensitivity of the photosensitive material F to be processed, which is supplied from, is compared, and the drive of the motor 33 of the light amount adjusting filter 17 is controlled so that the two match.

That is, the digital data (the amount of laser light currently entering the light amount sensor 41) taken in from the A / D converter 53 is converted into the photosensitive material F to be processed.
Motor 33 for matching the appropriate amount of light according to the sensitivity of
The rotation amount is calculated, and the motor 33 is controlled by the rotation amount.

At this time, if there is a large difference between the light quantity of the laser light currently incident on the light quantity sensor 41, which is taken in from the A / D converter 53, and the appropriate light quantity according to the sensitivity of the photosensitive material F to be processed. , The motor 33 is rotated at a high speed, and if the difference between the light amount of the laser light currently incident on the light amount sensor 41 and the appropriate light amount according to the sensitivity of the photosensitive material F to be processed becomes small, the motor 33 is rotated at a low speed. The control may be performed by rotating with to finely adjust the light amount.

Further, the light quantity adjustment switching control section 52 takes in a signal from the limit switch 38, recognizes the current state of the coarse adjustment filter 31 according to the signal, and detects the type of the photosensitive material F from the system 70. ND for coarse adjustment according to
The state of the filter 31 and the current rough adjustment ND filter 3
The rotary solenoid 34 may be controlled to be driven only when the state 1 does not match.

The control unit 50 is a ROM in which processing procedures (programs) executed by the control unit 50 are stored in advance.
(Read-only memory), CPU (central processing unit) that executes programs stored in ROM, and RAM (random memory) that temporarily stores data being processed.
Access memory) and the like. The microcomputer is installed inside the exposure head 3.

By the way, the A / D converter 53 outputs, for example, 0 to 8 V (voltage value) from 0 to 1023 (10 bits).
Consider the case of converting to. At this time, the light amount adjustment switching control unit 52 changes the light amount by a full bit (0 to 0).
1023), the C / V converter 42
The voltage value corresponding to the change in the amount of light output from is required to be expanded to the full range (0 to 8V). For example, the resistance value of the feedback resistor is set so that the C / V converter 42 converts TK ₂ into 8 V with respect to the light amount adjustment widths TK _{1 to} TK ₂ (see FIG. 20) of the highly sensitive photosensitive material F. It is preferable.

However, the conversion gain (resistance value of the feedback resistance) is set small in the conventional apparatus for processing the low-sensitivity photosensitive material F. Therefore, when trying to process a high-sensitivity photosensitive material with this conventional apparatus,
The light amount widths of TK _{1 and} TK ₂ are not expanded to the full range, but are converted to 0V to 2V, for example. In such a case, the light amount adjustment switching control unit 52 has to recognize the light amount widths of TK ₁ to TK ₂ from 0 to 255, as shown in FIG. 13, and corresponds to a certain data (for example, 128). light quantity TK ₁₁ ~TK _12, and the width TK ₁₁ of this amount -
Since the TK ₁₂ becomes wider, it becomes impossible to discriminate the change in the light amount in detail.

If a low-sensitivity photosensitive material F is to be processed by a conventional apparatus which processes a high-sensitivity photosensitive material F, the range is immediately exceeded (TK ₅ ...
It becomes TK ₄ ). At this time, the A / D converter 53 causes a conversion error or is converted into 1023, and in either case, the light amount adjustment switching control unit 52 cannot identify the light amounts of TK _{5 to} TK ₄ .

On the other hand, since the resistance value of the feedback resistor can be selected according to the type of the photosensitive material F as in this embodiment, the photosensitive material F of each type is selected.
Light amount adjustment width _{(TK 1 ~TK 2, TK 3} ~TK 4) the resistance of each feedback resistor 44 and 45 so as to convert the state close full range or in each R1, R2
Can be set, the light quantity adjustment switching control unit 5
In No. 2, regardless of the type of the photosensitive material F, the light amount adjustment width of the photosensitive material F can always be recognized in a state where it is expanded to a full bit or in a state close to that, and the light amount sensor 41
The amount of light incident on can be identified in detail. Therefore, the light amount adjustment of the light amount adjustment filter 17 can be accurately performed.

In order to make the minimum value (TK ₁ , TK ₃ ) of the appropriate sensitivity of each type of photosensitive material F correspond to the lower limit value (for example, 0V) of the input range of the A / D converter 53,
It is also possible to attach a difference circuit that makes a difference between a voltage value output from the C / V converter 42 and a predetermined voltage value, and input the voltage value output from the difference circuit to the A / D converter 53. That is, the voltage value V _IN input to the A / D converter 53 can be expressed by the following equation. _{V IN = (RR × I)} - V C ......... (1) However, RR is the resistance value of the feedback resistor connected to the C / V converter 42, V _C, the voltage is subtracted in difference circuit It is a value.

In the second embodiment, the voltage value corresponding to the light quantity detected by the light quantity sensor 41 is converted into digital data, and the light quantity adjustment of the light quantity adjusting filter 17 is performed based on the digital data. However, the control unit 50 may be configured by a control circuit that adjusts the light amount of the light amount adjusting filter 17 with the voltage value (analog data) as it is.

The configuration of the light quantity adjusting filter 17 in the first and second embodiments is not limited to the configuration shown in FIG. For example, the light amount adjustment filter, which is a combination of the two deflection filters 111 and 112 shown in FIG. 19B, adjusts the light amount for the photosensitive material F of the same type, and in FIG. 4 (and FIG. 10). The ND filter 31 (, 31b) for coarse adjustment described may be combined to configure the light amount adjusting filter 17, or the light amount continuous adjusting device proposed by the applicant of the present application in Japanese Patent Application No. 4-93100 may be finely adjusted. It is used as a filter for adjustment, and the N for coarse adjustment is added to this.
The light quantity adjusting filter 17 may be configured by combining the D filters 31 (, 31b). Also, at this time, FIG.
It is also possible to carry out a modification as described above.

Further, the light amount adjusting filter 17 may be constituted by a variable ND filter in which ND filters for adjusting the light amount only to an appropriate light amount corresponding to the sensitivity of the photosensitive material F determined by each manufacturer are arranged at equal intervals. Good. For example, in FIG.
As shown in FIG. 4 (a), the appropriate amount of light of the high-sensitivity photosensitive material F is only TK ₁ , TK ₄₁ , TK ₄₂ , and TK ₂ , and the appropriate amount of light of the low-angle photosensitive material F is TK ₃ , TK. ₄₃ , T
When only K ₄₄ , TK ₄₅ , TK ₄₆ , TK ₄₇ , TK ₄₈ , and TK ₄ are taken, as shown in FIG. 14B, the ND filters ND11 to ND22 have respective light amounts TK ₁ and T
K ₄₁ , TK ₄₂ , TK ₂ , TK ₃ , TK ₄₃ , TK ₄₄ , TK
_The attenuation rate is adjusted so as to be adjusted to ₄₅ , TK ₄₆ , TK ₄₇ , TK ₄₈ , and TK ₄ (indicated by the output light quantity in parentheses in the figure). With this configuration, one variable N
Even with the D filters, the number of ND filters can be small. It should be noted that the drawing shows the case where it can be applied to two types of photosensitive materials F, but the same configuration can be applied to three or more types of photosensitive materials F as well. Also, FIG. 14 (c)
As shown in, a plurality of ND filters may be provided adjacent to each ND filter (for example, ND11) for finely adjusting the light amount adjustment by the ND filter ND11. With this configuration, it is possible to finely adjust the light amount centered on a predetermined appropriate light amount.

When the light amount adjusting filter as described above is incorporated in the image output device, each motor or rotary solenoid for adjusting the light amount by each light amount adjusting filter is manually operated, or The light amount adjustment switching controller 53 drives and controls the light amount adjustment.

Next, the configuration of the third embodiment device of the present invention will be described. This third embodiment device is the same as the photosensitive material F of the same type.
However, it is intended for a photosensitive material F of a type having a wide light amount adjustment range. The third embodiment device has the same configuration as the first and second embodiment devices,
It is characterized in that the resistance values of a plurality of feedback resistors switched and connected to the C / V converter 42 are adjusted as follows. In the third embodiment, the light amount adjusting filter 17 need not be provided with the coarse adjusting filter 31.

For example, as shown in FIG. 15, the resistance value of the feedback resistance in the photosensitive material F of the kind having the light quantity adjustment range of TK ₂₁ to TK ₂₃ is the light quantity adjustment range of TK ₂₁ to TK.
₂₂ is set to be smaller than the resistance value of the feedback resistance in the photosensitive material F of a certain type. That is, in FIG.
As shown in, the slope of the light amount / voltage is gentler in the former case.

At this time, as shown in FIG. 16, for example,
The light quantity corresponding to the voltage V ₁ -V ₂ is TK _24-
In contrast to TK ₂₅ , the latter is TK ₂₆ to TK ₂₇ , and the width of the light quantity corresponding to the same voltage width is wide and narrow. That is, the former means that it is difficult for the latter to distinguish the change in the light amount with respect to the change in the voltage value. Further, when the voltage value is converted to digital data as in the above-described second embodiment, the change width of the light quantity with respect to the digital data becomes wide in the former case, so the light quantity adjustment switching control unit 52
This leads to the problem that it is not possible to discriminate the change in the amount of light.

Therefore, the resistance values of, for example, two fordback resistors, which are switchably connected to the C / V converter 42, are set as follows. That is, as shown in FIG. 17, the resistance value of the first feedback resistor is set so as to convert the light amount up to TK ₃₁ into a full range of voltage (V _{0 to} V _F ), and the resistance value of the second feedback resistor is set. Is set so that the light amount up to TK ₂₃ is converted into the full range of voltage. If the light quantity is TK ₂₁ or more and less than TK ₃₁ , the first feedback resistance is connected to the C / V converter 42, and if the light quantity is TK ₃₁ or more and TK ₂₃ or less, the second feedback resistance is C / V converter 42
Select to connect to. As a result, the change width of the light quantity with respect to the change of the voltage value or the change width of the light quantity with respect to the digital data can be narrowed,
A filter for light quantity adjustment 1 that can accurately identify changes in light quantity.
The light quantity adjustment by 7 can be performed accurately.

In this case as well, the configuration may be such that a difference circuit for realizing the equation (1) described in the second embodiment is additionally provided.

Further, the arrangement positions of the light amount adjusting filter 17 and the light amount detecting mechanism (in particular, the light amount sensor 41) are not limited to the arrangement positions described in the above-mentioned first embodiment device. For example, the gas laser 11 and the beam splitter 12
And the light amount adjusting filter 17 and the light amount sensor 41 are arranged in that order between the two, and the light amount is adjusted before being split into a plurality of laser beams, and the adjusted light amount is received by the light amount sensor 41. May be. The light amount sensor 41 needs to be configured to be retracted from the optical path during exposure, as in the case of being attached to the shutter 22 driven by the rotary solenoid 23.

Further, the structure of the light amount detecting mechanism in each of the above-mentioned embodiments is not limited to the structure shown in FIG. For example, as shown in FIG. 18A, a plurality of C / V converters 42a, 42b, ... To which feedback resistors 44, 45, ..., 49 having different resistance values R1, R2 ,. , 42n may be synchronously switched by the switches SW2 and SW3.

Further, as shown in FIG. 18B, a feedback resistor and a C / V converter 42 may be connected so that the switch SW4 selects the output voltage. At this time, the terminal Oa outputs the voltage value (V = R1 × I) whose resistance value is converted by R1, and the terminal Ob outputs the voltage value whose resistance value is converted by ((R1 + R2) / R2). And the resistance value is ((R3 + R4) from the terminal Oc.
The voltage value converted in / R4) is output. It should be noted that the figure shows a case where three types of conversion gains (resistance values) are switched, but the same configuration can be applied when switching two types or four or more types of conversion gains (resistance values). It should be noted that when applied to the apparatus of the second embodiment, FIG.
In (a) and (b), the output voltage value is given to the A / D converter 53 instead of the display device 43.

Further, in order to emit a plurality of laser beams and switch ON / OFF of each laser beam, the gas laser 11 and the beam splitter 1 are used in each of the above-mentioned embodiments.
2. Although the AOM 13 is used, for example, a plurality of semiconductor lasers may be arranged in parallel, and each semiconductor laser may be separately oscillated.

Further, the invention is not limited to an apparatus that emits a plurality of laser beams and exposes a plurality of exposure dots in one exposure.
An image is recorded on the photosensitive material F by emitting one laser beam, exposing one exposure dot by one exposure, and repeating feeding in the main scanning direction and feeding in the sub scanning direction. The present invention can be similarly applied to the device.

Furthermore, even if the optical system (in each of the above-described embodiments, the first reduction lens, the zoom lens, and the second reduction lens) has a different configuration, the present invention is similarly applicable. You can

In each of the above embodiments, the photosensitive material F
An example of a device that attaches to the rotating drum 1 has been described,
The present invention can be similarly applied to image output devices having other configurations.

[0093]

As is apparent from the above description, according to the first aspect of the invention, the conversion gain for converting the light amount adjusted by the light amount adjusting filter and applied to the photosensitive material into the voltage value. By configuring so that it can be switched and selected, it is possible to convert the light quantity of a photosensitive material whose light intensity adjustment range is remarkably different like different kinds of photosensitive materials into a voltage value with an appropriate conversion gain. Thus, the light amount being adjusted can be accurately identified, and the light amount adjustment by the light amount adjusting filter can be accurately performed. Further, the light amount during adjustment can be accurately identified even for the same type of light-sensitive material having a wide range of light amount adjustment.

Further, according to the invention of claim 2,
Since the exposure light quantity can be converted into a voltage value with an appropriate conversion gain, even if the voltage value is converted into digital data, A / D conversion can be performed in the full range / full bit or in a state close to it, and the light quantity adjustment is performed. In the switching control unit,
The amount of light being adjusted can be accurately identified, and the amount of light can be accurately adjusted by the light amount adjustment filter.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of an image output apparatus according to a first embodiment of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a diagram showing an internal configuration of an exposure head of the first embodiment apparatus.

FIG. 4 is a diagram showing a configuration of a light amount adjustment filter of the first embodiment device.

FIG. 5 is a diagram for explaining light amount adjustment by a light amount adjustment filter.

FIG. 6 is a diagram showing a configuration of a modified example of the light amount adjusting filter of the embodiment apparatus.

FIG. 7 is a diagram showing a configuration of a light amount detection mechanism.

FIG. 8 is a diagram showing a circuit configuration of a light amount detection mechanism.

FIG. 9 is a diagram showing a relationship between three types of photosensitive materials and an appropriate light amount of each photosensitive material.

FIG. 10 is a diagram showing a schematic configuration of a light amount adjustment filter for adjusting the light amount for three types of photosensitive materials.

FIG. 11 is a diagram showing a circuit configuration of a light amount detection mechanism that detects light amounts for three types of photosensitive materials.

FIG. 12 is a block diagram showing a schematic configuration of a second embodiment device.

FIG. 13 is a diagram showing a relationship between output data from an A / D converter and a light amount detected by a light amount sensor.

FIG. 14 is a diagram showing a configuration of a modified example of the light amount adjustment filter.

FIG. 15 is a diagram for explaining the configuration of the third embodiment device.

FIG. 16 is a diagram for explaining the configuration of the third embodiment device.

FIG. 17 is a diagram for explaining the configuration of the third embodiment device.

FIG. 18 is a diagram showing a configuration of a modified example of the light amount detection mechanism.

FIG. 19 is a diagram showing a configuration of a light amount adjustment filter of a conventional device.

FIG. 20 is a diagram showing a relationship between two types of photosensitive materials and an appropriate amount of light of each photosensitive material.

FIG. 21 is a diagram for explaining a problem of the conventional device.

[Explanation of symbols]

1 ... Rotating drum 3 ... Exposure head 17 ... Light amount adjustment filter 31 ... Coarse adjustment ND filter 32 ... Fine adjustment ND filter 33 ... Fine adjustment ND filter drive motor 34 ... Coarse adjustment ND filter drive rotary Solenoid 41 ... Light amount sensor 42 ... C / V converters 44, 45 ... Feedback resistance 51 ... Gain switching control unit 52 ... Light amount adjustment switching control unit 53 ... A / D converter F ... Photosensitive material SW1 ... Switch for resistance switching

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H01L 21/027 H04N 1/23 103 Z

Claims (2)

[Claims] 1. An image output device for recording an image on a photosensitive material by emitting exposure light from an exposure head according to an exposure pattern, and a light amount adjusting filter for adjusting the light amount of the exposure light applied to the photosensitive material, A light amount adjustment switching unit that switches the light amount adjustment amount of the light amount adjustment filter, and is adjusted by the light amount adjustment filter, and detects the light amount of the exposure light with which the photosensitive material is irradiated, and according to the detected light amount of the exposure light. An image output device comprising: a photoelectric conversion unit that outputs a voltage; and a gain switching unit that switches a conversion gain of the photoelectric conversion unit. 2. The image output device according to claim 1, wherein A / D conversion means for converting the voltage value (analog data) converted by the photoelectric conversion means into digital data, and sensitivity of the photosensitive material are set. Setting means, a gain switching control means for controlling switching of the conversion gain of the gain switching means according to the sensitivity of the photosensitive material, and the photosensitive material based on the digital data converted by the A / D converting means. And a light amount adjustment switching control unit for controlling switching of the light amount adjustment switching unit so as to adjust the light amount of the exposure light irradiated to the light amount to an appropriate light amount according to the sensitivity of the photosensitive material. Image output device.