JP2788180B2 - Image output device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field 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, for example, an image input device or an image data storage device. 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 according to the sensitivity of the photosensitive material.

[0002]

2. Description of the Related Art An image output apparatus of this type includes, 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. A plurality of laser beams (exposure beams) can be emitted from the exposure head, and these laser beams are turned on / off according to the exposure pattern.
The laser light that has been flipped and turned on exposes the photosensitive material. Then, by rotating the rotating drum, the positional relationship between the exposure head and the photosensitive material in the main scanning direction is displaced to perform exposure in the main scanning direction, and the exposure head is moved in the axial direction of the rotating drum to expose the exposure head. The exposure in the sub-scanning direction is performed by displacing the positional relationship of the photosensitive material in the sub-scanning direction.

[0003] Exposure (image recording) to a photosensitive material is performed by:
Since it is necessary to perform exposure with an appropriate light amount of the photosensitive material, the exposure head is provided with a light amount adjusting filter for adjusting the light amount of the laser light.

Incidentally, since the sensitivity of the photosensitive material varies from manufacturer to manufacturer, it is necessary to change the amount of light at the time of exposure according to the sensitivity of the photosensitive material. Therefore, the light amount adjustment filter of the conventional device is, for example, a variable ND (Neutral Density).
) It is composed of a filter, two deflection filters, etc., so that the light quantity can be continuously switched and adjusted.

As shown in FIG. 19A, the variable ND filter is coated with a plurality of types of ND filters 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 amount of the OLB is continuously switched and adjusted. In addition,
In the figure, reference numeral 102 denotes the lowest attenuation rate (the maximum output light amount).
Reference numeral 103 denotes an ND filter having the highest attenuation rate (minimum output light amount). Each of the ND filters constituting the variable ND filter 100 includes an ND filter 10.
2 to the ND filter 103 are arranged such that the attenuation rate gradually increases.

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

Further, some of the conventional apparatuses are provided with a light amount detecting mechanism for detecting the amount of light emitted from the exposure head to the photosensitive material, converting the detected amount of light into an electric signal and outputting the electric signal.

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

[0009]

However, the prior art 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 photosensitive materials such as a high sensitivity type such as a silver halide film and a low sensitivity type such as a printing plate. As described above, the sensitivity of each type of photosensitive material differs depending on the photosensitive material manufacturer. FIG. 20 shows the relationship between each type of photosensitive material and the appropriate light amount of each photosensitive material.

Incidentally, in the conventional apparatus, the apparatus is configured so that an image can be recorded on the same kind of photosensitive material. That is, for example, an image output apparatus for a photosensitive material of high sensitivity, the light quantity adjustment filter is adapted to perform the light amount adjustment in the proper quantity range for each manufacturer (TK ₁ ~TK _2).

Therefore, when an image is to be recorded by a conventional apparatus on a photosensitive material having a remarkably different sensitivity (appropriate light amount), such as a photosensitive material of a type different from the type of photosensitive material to be processed by the conventional apparatus, first, a light amount adjustment is performed. It is necessary to change the light intensity adjustment width of the filter for the type of photosensitive material.
This means, for example, that the variable ND filter (see FIG. 19A) is divided into two regions, and in one region, the light amount adjustment (TK _{1 to} TK ₂ ) for the high-sensitivity photosensitive material is continuously performed, in the other region, it may also be addressed by using a light quantity adjustment filter configured to continuously perform the photographic material of low sensitivity light amount (TK ₃ ~TK _4).

However, such a case has the following problem.

For example, in an apparatus configured to process a high-sensitivity photosensitive material (silver salt film or the like), FIG.
As shown in (a), the conversion gain is adjusted to be relatively large so that a light amount change in a low range can be identified with high accuracy. The light amounts TK ₁ and TK ₂ in the figure are the same as the light amounts shown in FIG. Therefore, if an image is recorded on a low-sensitivity photosensitive material (printing plate or the like) with this apparatus, the above-mentioned TK ₂
Much more than greater quantity T ₃ ~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 that the light amount cannot be properly adjusted by the light amount adjusting filter.

On the other hand, in an apparatus configured to process a low-sensitivity photosensitive material, as shown in FIG. 21 (c), a change in the amount of light in a high range is prevented from being over-ranged and can be accurately identified. The conversion gain is adjusted to be relatively small. Accordingly, in this apparatus, when wishing to make a picture recording on a photosensitive material of high sensitivity, amount much smaller than the TK ₃ T K ₁ ~TK ₂ (see FIG. 20), into an electric signal by the conversion gain conversion Figure 21 (d)
As shown in, the inclination of the change in the electrical signal with respect to the change of the light amount is small, change in light quantity (e.g., TK ₆ through T
Change in the level of the electrical signal to the K ₇₎ (SD ₁ ~SD
₂ ) has a problem that it is difficult to identify.

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

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

[0017]

The present invention has the following configuration in order to achieve the above object. That is, the invention according to claim 1 is an image output device that emits exposure light from an exposure head according to an exposure pattern and records an image on the photosensitive material, and adjusts the amount of exposure light applied to the photosensitive material. An adjustment filter, a light amount adjustment switching unit for switching a light amount adjustment amount of the light amount adjustment filter, and a light amount of exposure light which is adjusted by the light amount adjustment filter and is applied to the photosensitive material. Photoelectric conversion means for outputting a voltage according to the amount of light,
Gain switching means for switching the conversion gain of the photoelectric conversion means.

[0018] Further, an invention according to claim 2, in the image output apparatus according to claim 1, A / D converter for converting the converted voltage value by the photoelectric conversion means (analog data) into digital data means, setting means for setting the sensitivity of the sensitive light material, in accordance with the sensitivity of the photosensitive material, and the gain switching control means for controlling the switching of the conversion gain of the gain switching means, converted by the a / D conversion means based on the digital data, the light amount of the exposure light irradiated on the photosensitive material, said to be adjusted to a proper amount of light corresponding to the sensitivity of the photosensitive material, light amount adjustment switch control controls the switching of the light amount adjusting switching means Means.

[0019]

The operation of the first aspect of the invention is as follows. The light amount of the exposure light, which is adjusted by the light amount 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, according to the voltage value converted by the photoelectric conversion unit, the light amount adjustment switching unit sets the light amount adjustment switching unit so that the light amount of the exposure light applied to the photosensitive material becomes an appropriate light amount corresponding to the sensitivity of the photosensitive material to be processed. The light amount adjustment amount of the adjustment filter is switched and adjusted.

According to a second aspect of the present invention, the voltage value converted by the photoelectric conversion means is converted into digital data.
Based on the digital data, the light amount adjustment amount of the light amount adjustment filter is automatically adjusted. The 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 supplied to the light quantity adjustment switching control means. At this time, the conversion gain of the photoelectric conversion means is switched by the gain switching control means in accordance with the sensitivity of the photosensitive material set by the setting means. The light amount adjustment switching control unit switches the light amount adjustment switching unit so as to adjust the light amount of the exposure light applied to the photosensitive material to an appropriate light amount according to the sensitivity of the photosensitive material based on the provided digital data. Control.

[0022]

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. FIG.

The apparatus of the first embodiment can be used both for recording an image on a photosensitive material having a high sensitivity (for example, a silver halide film) and for recording an image on a photosensitive material having a low sensitivity (for example, a printing plate). . Further, the apparatus of the first embodiment is configured to manually adjust the light amount. Further, the first embodiment apparatus (image output apparatus) constitutes a part of an image recording system (hereinafter simply referred to as "system") including an image input apparatus (or image data recording apparatus) and a photosensitive material supply apparatus. It is a device to do. That is, image recording processing information such as 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 drawing, reference numeral 1 denotes a rotating drum. The photosensitive material F supplied from a photosensitive material supply device (not shown) is suction-held on the peripheral surface of the rotary drum 1 to record an image 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 rotating drum 1. The exposure head 3 is screwed to 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.
The rotation of the screw shaft 4 by the motor 6 moves the exposure head 3 in the axial direction of the rotating drum 1. That is, when an 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 performs sub-scan feed with respect to the photosensitive material F sucked and held on the peripheral surface of the rotary drum 1. You. 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. In addition, as described later, the gas laser 1
The laser light emitted from the light source 1 is transmitted to the beam splitter 12
In FIG. 3, only the optical axis is drawn because the drawing is complicated.

A gas laser (for example, an argon laser) 11 is attached to the exposure head 3 so that the emission direction of the laser beam is parallel to the axis of the rotating drum 1. The laser light emitted from the gas laser 11 is split into a plurality (for example, 10) of laser lights by a beam splitter 12 and is incident on an acousto-optic modulator (AOM) 13. The AOM 13 independently modulates (ON / OFF) each laser beam incident from the beam splitter 12 according to an 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 optical path of each laser beam emitted from the AOM 13 is turned back by the mirrors 14 and 15 in the direction opposite to the laser beam emitting direction (right direction in FIG. 3) (left direction in FIG. 3) and parallel to the first laser beam. The light enters the reduction lens system 16. Each laser beam emitted from the first reduction lens system 16 is incident on a filter 17 for adjusting the amount of light, is adjusted to an appropriate amount of light in accordance with the sensitivity of the photosensitive material F sucked and held by the rotating drum 1, and then adjusted to a zoom lens. 18 is incident. Zoom lens 1
Each laser beam emitted from 8 passes through a lens 19 constituting a second reduction lens system, and has an optical path of 90 ° by a mirror 20.
After being turned back, the image is formed on each exposure dot of the photosensitive material F sucked and held on the rotating drum 1 via the image forming lens 21 constituting the second reduction lens system. Note that 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 F during standby. The first reduction lens system 16, the zoom lens 18, and the second reduction lens system (the lens 19 and the imaging lens 21) determine the distance (for example, 15 mm) between the laser beams split by the beam splitter 12. Exposure dot interval (for example, 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 a main part of the present invention, for detecting the light amount of the laser light irradiated on the photosensitive material F, the light amount of which is adjusted by the light amount adjusting filter 17, is provided near the shutter 22. However, this configuration will be described later.

Next, the configuration of the light amount adjusting filter 17 will be described with reference to FIGS. FIG. 4 is a diagram showing a configuration of a light amount adjusting filter of the first embodiment device, and FIG.
FIG. 3 is a diagram for explaining light amount adjustment by a light amount adjustment filter.

As shown in FIG. 4, the light amount adjusting filter 17 is composed of an ND filter 31 for coarse adjustment and an ND filter 32 for fine adjustment. The fine adjustment ND filter 32 has the same configuration as that of the variable ND filter described with reference to FIG. 19A, and as shown in FIGS. the light quantity adjustment is performed so the photosensitive material F, the output light amount TK ₃ through T
Plural kinds of ND filters to adjust the K ₄ is are coated in a circumferential direction. Drive motor 33 for fine adjustment N
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 maker of the same type of photosensitive material F.

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

When exposing the photosensitive material F of low sensitivity (having a high appropriate light amount), the rotary solenoid 34 is used.
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. A state in which the ND filter having the highest attenuation rate in the adjustment ND filter 21 is arranged on the optical path)
The rotation is performed during 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 a photosensitive material F having a high sensitivity (low appropriate amount of light), the rotary solenoid 34 is driven, and as shown by a two-dot chain line in FIG. By arranging them on the optical path, the light amount adjustment is performed 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. It is. In the figure, TK ₁ , TK ₂ , TK ₃ , TK ₄
Is the same as the light amount shown in FIG.

When exposing the photosensitive material F of high sensitivity, 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.
2 can be finely adjusted, so the coarse adjustment ND filter 3
1 is {(TK ₃ -TK ₁ ) / TK ₃ } or more,
{(TK ₄ −TK ₂ ) / TK ₄ } or less. For example, as shown in FIG. 5 (b), when the attenuation factor of the coarse adjustment ND filter 31 _{{(TK 4 -TK 2) /} TK 4} is fine adjustment ND filter 32 a theta _S2 ° ~ Θ _E °
To adjust the light amount of the photosensitive material F with high sensitivity.

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

On the other hand, if the sensitivity of the photosensitive material F has a large variation in sensitivity among manufacturers, 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 configured so that the light amount adjustment (TK _{1 to} TK ₂ ) of the photosensitive material F with high sensitivity can be performed.

In this embodiment, the motor 33
The rotation driving of the rotary solenoid 34 and the driving of the rotary solenoid 34 are detected by a light amount detection mechanism described later, and are manually performed by an operator from the operation switch 35 based on data displayed on the display device.

The lamps 36 and 37 are used for rough adjustment ND.
This is for notifying the operator of the state 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
8, the lever 38a is pushed down, and the lamp 36 is turned on.
Further, the ND filter 32 for fine adjustment has the highest attenuation rate N
When the D filter is placed 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.
The rotary solenoid 34 corresponds to a light amount adjustment switching unit in the present invention.

As shown in FIG. 6, an ND filter 31a having the same configuration as that of the ND filter 31 for coarse adjustment is provided, and the ND filter 31a and the ND filter 32 for fine adjustment are used to form each type of photosensitive material F. You may comprise so that light quantity adjustment may be performed. In this case, the attenuation factor of the ND filter 31a is {TK _{4 −} {(TK ₃ × TK ₄ )} / TK ₄ . With such a configuration, finer light amount adjustment can be performed. Needless to say, two or more ND filters 31a may be provided, and the ND filter 31a and the ND filter 32 for fine adjustment may be used to adjust the light amount of each type of photosensitive material F.

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

As shown in FIG. 7, a light amount sensor 41 such as a solar cell is mounted on 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 light quantity of the 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 is provided. Data indicating the amount of light incident on 41 is displayed on the display device 43.

In this embodiment, the C / V converter 4
2, two feedback resistors are connected, and these feedback resistors 44 and 45 are switched by a switch SW1 in accordance with the type (sensitivity) of the photosensitive material F to be processed.
Either one can be selectively switched.
The switching operation of the switch SW1 is configured to be manually performed by an operator.

The feedback resistor 44 has a large resistance value R1 so that the amount of light adjusted with respect to the photosensitive material F having high sensitivity can be accurately detected.
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 resistance 44 is C /
The relationship between the current I and the output voltage V in the state where the output voltage V is 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 a photoelectric conversion means in the present invention. Switching of the resistance value corresponding to the conversion gain, that is,
A plurality of (two in this embodiment) feedback resistors 44 and 45 are provided in accordance with the number of types of photosensitive material F.
Connect to 2, configured for selecting switching them off I readback resistor 44 and 45 in the switch SW1 is equivalent to the gain switching means in the present invention.

Next, the operation of the worker and the accompanying operation of the embodiment will be described. The light amount adjusting operation using the light amount detecting mechanism and the light amount adjusting filter 17 is performed in the following cases.

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

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

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

Next, the operator operates an operation switch (not shown) to drive the rotary solenoid 23, close the shutter 22, dispose the light amount sensor 41 on the optical path, and branch the beam with the beam splitter 12. The ON / OFF control unit 13a controls to turn on only one laser beam incident on the light amount sensor 41 and to turn off all other nine laser beams out of the laser beams thus applied.

As a result, the amount of one laser beam applied to the photosensitive material F is detected, and data indicating the detected amount of light is displayed on the display device 43. At this time, since the feedback resistors 44 and 45 have been switched to ones corresponding to the type of the photosensitive material F, there is no overrange, and a change in the amount of light 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, and while rotating the fine adjustment ND filter 32, the light amount detected by the light amount sensor 41, in other words, Then, 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 worker in the case of the above (2) and the operation of the embodiment apparatus accompanying the operation 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 ND filter 31 for coarse adjustment (whether placed on the optical path or retracted) remain as they are. Since it is good, the operator does not perform any operation on these.

Then, the shutter 22 is closed and ON / OFF is performed so that only one laser beam is incident on the light amount sensor 41.
While instructing the OFF control section 13a and observing the data displayed on the display device 43, the operation switch 35 is used for fine adjustment so as to adjust the light amount to an appropriate amount in accordance with 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 detection mechanism for adjusting the light amount can be switched and selected according to the type (sensitivity) of the photosensitive material F to be processed. Even when both are used for image recording of different photosensitive materials, optimal C / V conversion can be performed, and light amount adjustment by the light amount adjusting filter can be performed with high accuracy.

In the above-described first embodiment and the following second embodiment, the apparatus is constructed so as to be compatible with two types of photosensitive materials F. However, more types of photosensitive materials F, for example, as shown in FIG. As shown in (1), the apparatus can be configured so that it can be used for image recording processing of three types of photosensitive materials F.
In this case, the light amount adjusting filter 17 may be configured as shown in FIG. 10, and the light amount detecting mechanism may be configured as shown in FIG.

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

The attenuation amount of the coarse adjustment filters 31 and 31b is adjusted. For the photosensitive material F of the medium sensitivity, the fine adjustment ND filter 32 is used for the laser light attenuated by the coarse adjustment ND filter 31b. The light amount is adjusted, and for the photosensitive material F with high sensitivity, the fine adjustment ND is applied to the laser light attenuated by the coarse adjustment ND filters 31 and 31b.
The light quantity adjustment may be performed by the filter 32.

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

Next, in the light amount detection mechanism shown in FIG.
/ V converter 42 has three types of feedback resistors 44
(Resistance value R1), 45 (resistance value R2), 46 (resistance value R
3) and connect the C / V converter 42 with the switch SW1.
This is a configuration in which the feedback resistor connected to the switch is switched and selected. Note that the resistance value R3 of the feedback resistor 46 is
The size is set so that the amount of light for the medium-sensitive photosensitive material F can be accurately detected.

In order to use the light-sensitive material F for processing four or more kinds of photosensitive materials F, the light amount adjusting filter 17 may be provided by providing a new coarse adjusting filter in the same manner as described above. The light amount detection mechanism may be connected by connecting a feedback resistor to the C / V converter 42 in accordance with 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 of the present invention will be described. The device of the second embodiment corresponds to the invention described in claim 2, and in the device of the first embodiment,
An A / D converter as A / D conversion means for converting a voltage value output from the light amount detection mechanism into digital data, and a control unit for automatically adjusting the light amount of the light amount adjusting filter 17 based on the digital data. Is provided.

The connection state between 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 section 50 is composed of a gain switching control section 51 as gain switching control means and a light quantity adjustment switching control section 52 as light quantity adjustment switching control means.

When the type of the photosensitive material F is notified from the system 70 corresponding to the setting means of the present invention, the gain switching control unit 51 supplies a feedback resistance suitable for the notified type of the photosensitive material F to the C / V converter. Switching of the switch SW1 of the light amount detection mechanism is controlled so as to connect to the switch. Then, the rotary solenoid 23 is driven to close the shutter 22, the light quantity sensor 41 is disposed on the optical path of the laser light, and only one laser light is supplied to the light quantity sensor 41.
The ON / OFF control unit 13a is controlled so as to make the light incident on the light source. 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 light the ND filter 31 for coarse adjustment. Place it on the street,
Control whether to evacuate. At this time, C
The voltage value corresponding to the amount of light received by the light amount sensor 41 and output from the / V converter 42 is output to the A / D converter 53
Is converted to digital data. The light amount adjustment switching control unit 52 transmits the digital data and the system 70
Is compared with an appropriate light amount corresponding to the sensitivity of the photosensitive material F to be processed, supplied from the printer, and the driving of the motor 33 of the light amount adjusting filter 17 is controlled so that the two coincide with each other.

That is, the digital data (the amount of laser light currently incident on the light amount sensor 41) fetched from the A / D converter 53 is converted into the photosensitive material F to be processed.
Motor 33 for matching an appropriate amount of light according to the sensitivity of
Is obtained, and the motor 33 is controlled to be driven by the amount of rotation.

At this time, if there is a large difference between the light amount of the laser light, which is taken in from the A / D converter 53 and is currently incident on the light amount sensor 41, and the appropriate light amount corresponding to the sensitivity of the photosensitive material F to be processed. If the difference between the light amount of the laser beam currently incident on the light amount sensor 41 and the appropriate light amount corresponding to the sensitivity of the photosensitive material F to be processed becomes small, the motor 33 is rotated at a low speed. May be controlled so that the light amount is finely adjusted.

The light amount adjustment switching control unit 52 receives a signal from the limit switch 38, recognizes the current state of the coarse adjustment filter 31 according to the signal, and determines 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 coarse adjustment ND filter 3
The control may be performed so that the rotary solenoid 34 is driven only when the state of 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), a CPU (central processing unit) for executing a program stored in the ROM, and a random access memory (RAM) for temporarily storing data being processed.
Access memory) and the like. The microcomputer is provided in the exposure head 3.

The A / D converter 53 converts, for example, 0 to 8 V (voltage value) to 0 to 1023 (10 bits).
Consider the case of converting to At this time, the light amount adjustment switching control unit 52 uses a full bit (0 to
1023), the C / V converter 42
The voltage value corresponding to the change in the amount of light output from the device needs to be developed in the full range (0 to 8 V). For example, with respect to the light quantity adjustment width TK ₁ ~TK ₂ of the photosensitive material F of the high sensitivity (see FIG. 20), the resistance value of the feedback resistor so as to convert the TK ₂ to 8V in C / V converter 42 is set Is preferred.

However, the conversion gain (the resistance value of the feedback resistor) is set small in the conventional apparatus for processing a low-sensitivity photosensitive material F. Therefore, when processing a high-sensitivity photosensitive material with this conventional apparatus,
Amount width of TK ₁ ~TK ₂ is not expanded to the full range, for example, it will be converted to 0V to 2V. In such a case, as shown in FIG. 13, the light amount adjustment switching control unit 52 must recognize the light amount width of TK ₁ to TK ₂ from 0 to 255, and corresponds to certain data (for example, 128). light quantity TK ₁₁ ~TK _12, and the width TK ₁₁ of this amount -
Since the TK ₁₂ becomes wide, it is impossible to finely identify a change in the light amount.

[0074] Further, if trying to process the photosensitive material F in the low-sensitivity conventional apparatus to be processed photosensitive material F of the high sensitivity, the immediate range over (FIG. 21 (d) TK ₅ ~
TK ₄ ). At this time, the A / D converter 53, or a conversion error, will be converted to 1023, in any case, it is impossible to identify the light intensity of the light quantity adjusting the switching control unit 52 in TK ₅ ~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 the present embodiment, each type of photosensitive material F
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 amount adjustment switching control unit 5
In No. 2, the light amount adjustment width of the photosensitive material F can always be recognized in a state where the light amount adjustment width of the photosensitive material F is expanded to full bits or in a state close to it, regardless of the type of the photosensitive material F.
Can be finely identified. Therefore, the light amount of the light amount adjusting filter 17 can be adjusted with high accuracy.

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, 0 V) of the input range of the A / D converter 53,
A configuration may be adopted in which a difference circuit for subtracting a predetermined voltage value from the voltage value output from the C / V converter 42 is provided, and the voltage value output from the difference circuit is input 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) where RR is a resistance value of a feedback resistor connected to the C / V converter 42, and V _C is a voltage subtracted by the difference circuit. Value.

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

The configuration of the light amount adjusting filter 17 in the first and second embodiments is not limited to the configuration shown in FIG. For example, the light amount adjustment for the same type of photosensitive material F is performed by a light amount adjustment filter in which the two deflection filters 111 and 112 shown in FIG. 19B are combined. The light amount adjustment filter 17 may be configured by combining the coarse adjustment ND filters 31 (31b) described above, or the light amount continuous adjustment device proposed by the present applicant in Japanese Utility Model Application No. 4-93100 may be used. Adjustment filter, and the coarse adjustment N
The light amount adjusting filter 17 may be configured by combining the D filters 31 (31b). At this time, FIG.
It is also possible to carry out the modification as described in the 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 amount according to the sensitivity of the photosensitive material F for each predetermined manufacturer are arranged at equal intervals. Good. For example, FIG.
4 (a), the proper amount of the photosensitive material F highly _{sensitive, TK 1, TK 41, TK} 42, TK 2 only Torazu, proper amount of low angle of the photosensitive material F is, TK _3, TK ₄₃ , T
_{K 44, TK 45, TK 46} , TK 47, TK 48, if the TK ₄ only taken, as shown in FIG. 14 (b), the ND filter ND11~ND22 each light amount, TK _1, T
_{K 41, TK 42, TK 2} , TK 3, TK 43, TK 44, TK
_{45, TK 46, TK 47,} TK 48, ( in the figure each indicate an output light amount in parentheses) TK ₄ are adjusted attenuation factor to adjust the. With this configuration, one variable N
Even with the D filter, the number of each ND filter is small. Although the drawing shows a case where the present invention can be applied to two types of photosensitive materials F, the same configuration can be applied to three or more types of photosensitive materials F. FIG. 14 (c)
As shown in (1), a plurality of ND filters may be provided adjacent to each ND filter (for example, ND11) to finely adjust the light amount adjustment by the ND filter ND11. With this configuration, the light amount can be finely adjusted centered on a predetermined appropriate light amount.

When the above-mentioned light amount adjusting filter is incorporated in the image output device, the motors and rotary solenoids for adjusting the light amount by each light amount adjusting filter are manually operated, or The light amount adjustment switching control unit 53 drives and controls the light amount.

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

For example, as shown in FIG. 15, the resistance value of the feedback resistor in the photosensitive material F of the kind whose light amount adjustment width is TK ₂₁ to TK ₂₃ is such that the light amount adjustment width is TK ₂₁ to TK.
₂₂ is set to be smaller than the resistance value of the feedback resistance in the kind of photosensitive material F. That is, FIG.
As shown in the graph, the slope of the light quantity / voltage is gentler in the former case.

At this time, for example, as shown in FIG.
The light amount corresponding to the voltage between V _{1 and} V ₂ is TK _24-
Whereas a TK _25, the latter is TK ₂₆ ~TK _27, there is a wide or narrow the width of the light quantity corresponding to the same voltage range. That is, the former means that it is difficult to distinguish the change in the light amount with respect to the change in the voltage value from the latter. Further, when the voltage value is converted into digital data as in the above-described second embodiment, the change width of the light amount with respect to the digital data is wider in the former case.
This leads to a problem that a change in light amount cannot be distinguished finely.

[0084] Therefore, the C / V converter 42, which is freely connected to switch, for example, the resistance value of the two full I readback resistance was set as follows. That is, as shown in FIG. 17, the resistance of the first feedback resistor, configured to convert the up quantity TK ₃₁ full range of the voltage (V ₀ ~V _F), a second resistance value of the feedback resistor the set to convert to light intensity TK ₂₃ full range of voltage. Then, the amount of light TK ₂₁ or more, is less than TK _31, the first feedback resistor connected to the C / V converter 42, the amount of light is TK ₃₁ or more, if the TK ₂₃ or less, the second feedback resistor C / V converter 42
Select to switch to the connection. As a result, the width of change of the light amount with respect to the change of the voltage value or the width of change of the light amount with respect to the digital data can be reduced.
Filter 1 for light amount adjustment that can accurately identify changes in light amount
7 can be performed with high accuracy.

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

The arrangement positions of the light amount adjusting filter 17 and the light amount detection mechanism (particularly, the light amount sensor 41) are not limited to the arrangement positions described in the first embodiment. For example, a gas laser 11 and a beam splitter 12
The light amount adjusting filter 17 and the light amount sensor 41 are arranged in that order, the light amount is adjusted before the laser light is branched into a plurality of laser beams, and the adjusted light amount is received by the light amount sensor 41. You may. The light amount sensor 41 needs to be configured to be retracted from the optical path during exposure, for example, as attached to the shutter 22 driven by the rotary solenoid 23.

Further, the configuration of the light amount detection mechanism in each of the above embodiments is limited to the configuration shown in FIG.
Not something . For example, as shown in FIG. 18A, a plurality of C / V converters 42a, 42b,... Connected with feedback resistors 44, 45,..., 49 having different resistance values R1, R2,. it may be configured to switch synchronously with 42n in the switch SW2, SW3.

Further, as shown in FIG. 18B, a feedback resistor and a C / V converter 42 may be connected, and the output voltage may be selected by the switch SW4. At this time, a voltage value (V = R1 × I) whose resistance value is converted by R1 is output from the terminal Oa, and a voltage value whose resistance value is converted by ((R1 + R2) / R2) is output from the terminal Ob. And the resistance value from the terminal Oc is ((R3 + R4)
/ R4) is output. Although FIG. 2 shows a case where three types of conversion gains (resistance values) are switched, the same configuration can be applied to a case where two types or four or more types of conversion gains (resistance values) are switched. In the case where the present invention is applied to 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, in each of the above-described embodiments, the gas laser 11 and the beam splitter 1 are used.
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 individually oscillated.

The present 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 the main-scanning feed and the sub-scan feed. The present invention can be similarly applied to an apparatus.

Further, the present invention is similarly applicable even if the optical system (in each of the above embodiments, the first reduction lens, the zoom lens, and the second reduction lens) has a different configuration. Can be.

[0092] In each real施例above, it has been described taking an apparatus for mounting a photosensitive material F on the rotary drum 1 as an example, but the present invention to the image output device of the other configuration is similarly applied to Can be.

[0093]

As is apparent from the above description, according to the first aspect of the present invention, the conversion gain at the time of converting the amount of light, which is adjusted by the light amount adjusting filter and applied to the photosensitive material, into a voltage value is obtained. Can be selected by switching, the light amount of the photosensitive material whose light amount adjustment width is remarkably different like a different type of photosensitive material can be converted into a voltage value with an appropriate conversion gain. As a result, the light amount being adjusted can be identified with high accuracy, and the light amount can be accurately adjusted by the light amount adjusting filter. In addition, the light amount being adjusted can be identified with high accuracy even for the same kind of photosensitive material having a wide light amount adjustment width.

Further, according to the second aspect of the present invention,
Since the exposure light amount is configured to be converted to a voltage value with an appropriate conversion gain, even if the voltage value is converted to digital data, the A / D conversion can be performed in a full range / full bit or a state close to it, and the light amount can be adjusted. In the switching control section,
The light amount during the adjustment can be identified with high accuracy, and the light amount can be adjusted with a light amount adjusting filter with high accuracy.

[Brief description of the 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 adjusting 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 illustrating a configuration of a modification of the light amount adjustment filter of the embodiment device.

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

FIG. 8 is a diagram illustrating 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 adjusting filter for adjusting light amounts for three types of photosensitive materials.

FIG. 11 is a diagram illustrating 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 illustrating a schematic configuration of a second embodiment apparatus.

FIG. 13 is a diagram illustrating 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 illustrating a configuration of a modification of the light amount adjustment filter.

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

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 device of the third embodiment.

FIG. 18 is a diagram illustrating a configuration of a modification of the light amount detection mechanism.

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

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

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotary drum 3 ... Exposure head 17 ... Light amount adjustment filter 31 ... Coarse adjustment ND filter 32 ... Fine adjustment ND filter 33 ... Motor for driving fine adjustment ND filter 34 ... Rotary for driving coarse adjustment ND filter Solenoid 41 Light amount sensor 42 C / V converter 44, 45 Feedback resistance 51 Gain switching control unit 52 Light amount adjustment switching control unit 53 A / D converter F Photosensitive material SW1 Resistance switch

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04N 1/036 B41J 2/44 G03F 7/20 511 H01L 21/027 H04N 1/23 103

Claims (2)

(57) [Claims] 1. An image output device that emits exposure light from an exposure head according to an exposure pattern and records an image on a photosensitive material, comprising: a light amount adjustment filter that adjusts a light amount of the exposure light applied to the photosensitive material; A light amount adjustment switching unit for switching the light amount adjustment amount of the light amount adjustment filter; and a light amount of exposure light that is adjusted by the light amount adjustment filter and applied to the photosensitive material, and is detected in accordance with the detected light amount of the exposure light. An image output apparatus comprising: a photoelectric conversion unit that outputs a voltage; and a gain switching unit that switches a conversion gain of the photoelectric conversion unit. The image output apparatus according to claim 1, setting the A / D converting means for converting the converted voltage value by the photoelectric conversion means (analog data) into digital data, the sensitivity of the sensitive light material setting means for, in response to said sensitivity of the photosensitive material, and the gain switching control means for controlling the switching of the conversion gain of the gain switching means, based on the converted digital data at the a / D converting means, the photosensitive material the amount of the exposure light irradiated, the to adjust the proper amount of light corresponding to the sensitivity of the photosensitive material, comprising: a light amount adjustment switch control means for controlling the switching of the light <br/> amount adjusting switching means, the An image output device, comprising: