JP2001066718A - Image information reading method and device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form line light which is satisfactory in light utilization efficiency in an image information reading method and a device thereof, using a radiation solid body detector of an optical readout system having a stripe electrode. SOLUTION: A long-length type reflecting mirror 96, constituted by linearly arraying many minute projecting surfaces 98 in the length direction of the mirror 96 on its reflection surface 96a, is arranged so that the surface 96a may be opposed to the surface of a detector 30 and form a prescribed angle to the surface. A cylindrical lens 95 is arranged between the mirror 96 and the detector 30, so that a bus is in the same direction as that of the array of an element. A light beam P is made incident on the surface 96a from the side surface of the detector 30 and reflected toward the detector 30 by the surfaces 98, and by having the reflected light beam P converge on the detector 30 by the lens 95, a line light obtained by extending the light beam P in the array direction of the element of the detector 30 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical reading type image detector having an electric storage unit for accumulating an amount of electric charge corresponding to the amount of irradiated recording light as a latent image charge. And a method and apparatus for reading image information recorded as an electrostatic latent image on an image.

[0002]

2. Description of the Related Art Conventionally, apparatuses using an image detector, such as a facsimile, a copying machine, and a radiation imaging apparatus, are known.

For example, in a medical radiation imaging apparatus or the like, a photoconductor (layer) such as a selenium plate which is sensitive to radiation such as X-rays is provided in order to reduce a radiation dose received by a subject and improve diagnostic performance. An X-ray radiation solid state detector (electrostatic recording medium) having an optical readout method is used as an image detector, and the solid state radiation detector is irradiated with X-rays. The radiation image information is recorded as an electrostatic latent image in the power storage unit by accumulating the latent image charge in the power storage unit in the detector, and the radiation image information is recorded with the laser beam or the linear light beam. A method of reading radiation image information from the solid-state radiation detector by scanning the detector is known (for example, US Pat. No. 5,268,569, International Publication 199).
No. 59261, JP-A-9-5906, and Japanese Patent Application Nos. 10-271374 and 11-8 by the present applicant.
No. 7922).

[0004] Here, Japanese Patent Application No. 10-2 filed by the present applicant.
The radiation solid-state detectors described in JP-A-71374 and JP-A-11-87922 are: a first electrode layer having transparency to recording radiation, and irradiation of recording radiation transmitted through the first conductor layer. The recording photoconductive layer, which exhibits conductivity when received, acts substantially as an insulator for charges of the same polarity as the charges charged on the first electrode layer, and has a charge of the opposite polarity to the charges of the same polarity. In contrast, a charge transport layer that acts as a substantially conductive material, a reading photoconductive layer that exhibits conductivity by being irradiated with reading electromagnetic waves, and a second electrode layer that is transparent to reading electromagnetic waves. The signal charges (latent image charges) carrying image information are stored in a power storage unit formed at the interface between the recording photoconductive layer and the charge transport layer.

[0005] As a method of reading out signal charges in this detector, for example, an electrode (hereinafter also referred to as a reading electrode) of a second electrode layer has a plate-like shape, and a spot-like reading of laser or the like is performed on the reading electrode side. A method of detecting signal charges by scanning light (one mode of electromagnetic waves for reading), and a method of forming a reading electrode as a stripe electrode composed of a number of linear electrodes, in a direction substantially perpendicular to the longitudinal direction of the linear electrodes, ie, a line. There is a method of detecting signal charges by scanning line light (line-shaped reading light) extending in the direction in which the linear electrodes are arranged in the longitudinal direction of the linear electrodes.

[0006]

Here, in the case of using an optical reading type image detector having a stripe electrode as a reading electrode, a line light is formed by a non-coherent light source using, for example, a lamp or an LED. When the image detector is irradiated with the line light to obtain an image signal corresponding to the amount of the latent image charge stored in the power storage unit, it is difficult to converge the light, the light use efficiency is poor, and the intensity is sufficient. However, there is a problem that a large amount of electric power is required to obtain the line light.

The present invention has been made in view of the above circumstances, and when irradiating a line light to an optical reading type image detector having a stripe electrode, the light is easily converged and the light utilization efficiency is improved. It is an object of the present invention to provide an image information reading method and apparatus which can be improved.

[0008]

According to the present invention, there is provided an image information reading method, comprising: a two-dimensionally distributed power storage unit for storing charges carrying image information as latent image charges; and a latent image stored in the power storage unit. Using a light-reading type image detector in which a large number of linear electrodes for extracting electric signals of a level corresponding to the amount of electric charges are arranged substantially in parallel, a linear electrode extending in the direction in which the linear electrodes are arranged is used. Scanning the reading light (line light) in the longitudinal direction of the linear electrode, and acquiring an electric signal output for each linear electrode by the scanning, the image information is recorded as an electrostatic latent image in the power storage unit. An image information reading method for reading image information from a selected image detector, wherein a light beam is expanded in the direction in which the linear electrodes are arranged and converged in the scanning direction to obtain a linear read light (line light). Is formed.

In the image information reading method according to the present invention, a long reflecting mirror having a large number of minute convex surfaces arranged in a straight line is provided so as to be parallel to the arrangement direction of the linear electrodes and perpendicular to the surface of the image detector. In the plane, the micro-convex surface is arranged so as to face the surface so as to form a predetermined angle with respect to the surface, and the light beam is arranged so that the optical axis of the light beam is the same as the alignment direction. It is preferable that the light beam is expanded in the direction in which the linear electrodes are arranged by making the light beam incident on the long reflecting mirror and reflecting the light beam on the minute convex surface.

In the image information reading method according to the present invention, the cylindrical optical member is arranged so that the generatrix of the cylindrical optical member is the same as the direction in which the linear electrodes are arranged, and is enlarged in the direction in which the linear electrodes are arranged. It is desirable that a light beam is incident on the cylindrical optical member to form a linear reading light (line light).

In the image information reading method according to the present invention, the unevenness of the read image information due to the intensity distribution of the linear read light (line light) in the direction in which the linear electrodes are arranged is corrected. Is desirable.

An image information reading apparatus according to the present invention is an apparatus for realizing the above-described image information reading method, that is, a two-dimensionally distributed power storage unit for storing charges carrying image information as latent image charges, and the power storage unit An optical readout image detector in which a large number of linear electrodes for extracting an electric signal at a level corresponding to the amount of latent image charges accumulated in the optical readout system and a linear electrode extend in the direction in which the linear electrodes are arranged. Reading light irradiating means for scanning a line-shaped reading light (line light) in the longitudinal direction of the linear electrode to irradiate substantially the entire surface of the image detector; and outputting an electric signal output for each linear electrode by the scanning. An image information reading apparatus comprising: an image signal obtaining unit that obtains an image signal, wherein a reading light irradiation unit expands a light beam in a direction in which the linear electrodes are arranged and converges the light beam in the scanning direction to form a line. Equipped with an optical system that forms reading light (line light) It is characterized in that those were.

In the image information reading apparatus according to the present invention, the optical system includes a plurality of minute convex surfaces which are linearly arranged, and which is parallel to the arrangement direction of the linear electrodes and perpendicular to the surface of the image detector. Inside, it has a long reflective mirror arranged so that a small convex surface faces the surface and forms a predetermined angle with respect to the surface, and the optical axis is the same as the alignment direction As described above, it is preferable that the light beam incident on the long reflecting mirror is reflected by the minute convex surface to expand the light beam in the direction in which the linear electrodes are arranged.

In the image information reading apparatus according to the present invention, the optical system is arranged such that the generatrix is arranged in the same direction as the arrangement of the linear electrodes, and the light beam expanded in the arrangement direction of the incident linear electrodes. It is desirable to have a cylindrical optical member for forming a linear optical element.

In the image information reading apparatus according to the present invention, it is desirable that the reading light irradiating means includes a semiconductor laser emitting a light beam or a laser diode-pumped solid-state laser.

In the image information reading apparatus according to the present invention, the image carried by the electric signal acquired by the image signal acquiring means is caused by the intensity distribution of the line-shaped reading light (line light) in the arrangement direction of the linear electrodes. It is desirable to further include a correction unit for correcting unevenness of information.

[0017]

According to the image information reading method and apparatus of the present invention, the light beam emitted from the laser light source is expanded in the direction in which the linear electrodes are arranged and converged in the scanning direction to form line light. Therefore, the convergence of light is facilitated, and the light use efficiency can be improved.

In addition, a long reflecting mirror having a large number of minute convex surfaces arranged in a straight line is arranged as described above, and the light beam is reflected by the minute convex surface so that the light beam is aligned in the direction in which the linear electrodes are arranged. If the optical system is expanded to a smaller size, a compact optical system can be configured.

If a laser light source having a semiconductor laser or a laser-diode-pumped solid-state laser is used as a laser light source for emitting a light beam, line light having sufficient intensity can be formed with relatively small power.

Further, if the unevenness of the read image information due to the intensity distribution of the line light in the direction in which the linear electrodes are arranged is corrected, even if the light beam is formed in a line shape, the light intensity can be reduced. This eliminates the possibility that image unevenness due to distribution occurs.

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of an image information reading apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a laser diode pumped solid-state laser.
FIG. 3 is a diagram showing details of a reading light irradiating means used in the image information reading apparatus shown in FIG. 1, wherein a front view (A), a left side view (B), and an intensity distribution of a light beam are shown in a front view ( (C1)-(C3) shown corresponding to (A).

As shown in FIG. 1, the image information reading apparatus 1 according to the first embodiment has a solid-state radiation detector 30 as an image detector, a current detection circuit 70 as an image signal acquisition means, and a reading light irradiation. Means 80.

As shown in FIG. 1, the radiation solid state detector 30 has an electrode layer in which a number of elements (linear electrodes) 16a and 17a are alternately arranged in a stripe shape. As the element 16a, a material and a thickness having transparency to the reading light L2 are used. Element 1
7a is for outputting an electric signal of a level corresponding to the amount of latent image charges stored in the power storage unit formed substantially at the interface between the recording photoconductive layer and the charge transport layer in the solid-state radiation detector 30. Things. As the element 17a, a reading light
A material having a light-shielding property and a thickness for L2 is used, and the reading photoconductive layer 14 corresponding to the element 17a is used.
In this case, a charge pair for signal extraction is not generated (Japanese Patent Application No. 11-87922 filed by the present applicant).
No.).

The reading light irradiating means 80 reads a laser light source 81 disposed on the side surface of the solid-state radiation detector 30 and irradiates the solid-state radiation detector 30 as an image detector with a light beam emitted from the laser light source 81. An optical optical system 90 is provided.

As the laser light source 81, one having a semiconductor laser or a laser diode-pumped solid-state laser is used. Further, the peak wavelength is 400 nm corresponding to the photoconductive layer of the solid-state radiation detector 30 being a-Se.
The one that emits blue-violet light is used.

Here, as the semiconductor laser, either a vertical single mode semiconductor laser or a vertical multimode semiconductor laser may be used. Further, a vertical multi-mode oscillation may be performed by driving a vertical single-mode type semiconductor laser with a high frequency superimposed current.

As a laser-diode-pumped solid-state laser, a solid-state laser crystal to which a rare earth element such as neodymium is added, as shown in, for example, Japanese Patent Application Laid-Open No. 62-189783, is a light (laser beam) emitted from a laser diode. ), A nonlinear optical crystal is arranged in the resonator so as to obtain a laser beam having a shorter wavelength, and the solid-state laser beam is converted into a second harmonic (SHG; Se).
An SHG laser configured to perform wavelength conversion to cond harmonic generation may be used.

Further, as this SHG laser, FIG.
As shown in FIG.
The semiconductor laser light having a wavelength of 720 nm to 900 nm emitted from 0 is converted into a bulk type wavelength conversion element 1 made of an MgO—LiNbO 3 domain inverted bulk crystal via a wavelength selection element 101.
02, and is resonated in the wavelength conversion element 102 or passed in one pass, and the semiconductor laser light is irradiated with the second wavelength in the ultraviolet to blue wavelength band of 360 nm to 450 nm of half the wavelength.
It is possible to use a bulk direct conversion SHG laser which is converted into a harmonic to obtain a short wavelength laser beam. The output of the bulk direct conversion SHG laser can be changed according to the output of the semiconductor laser 100, and for example, an output of 1 mW to 100 mW can be obtained. In particular, if a bulk domain inversion crystal is used, it is possible to obtain SHG light of an arbitrary wavelength by changing the inversion period. Also, unlike a normal semiconductor laser, even if the SHG light returns to the semiconductor laser, the return light has a different wavelength from the semiconductor laser light, so that the semiconductor laser 100 does not generate noise due to instability due to the return light. So, read the SHG light
When used as L2, stable image reading is possible.

Alternatively, as shown in FIG.
Infrared (809 nm) of about W to 2 W to red (680 n
m), the solid-state laser crystal (Nd: YAG, Cr: LiCAF, etc.) 102 is excited by the broad-area semiconductor laser 110, and one end face of the solid-state laser crystal and the mirror 1 are excited.
06, a solid-state laser beam is oscillated, and a solid-state laser beam is oscillated by inserting a MgO-LiNbO3 domain-inverted bulk type wavelength conversion element 103, a Brewster plate 104, an etalon 105, etc. inside the resonator. S
It is also possible to use an SHG solid-state laser that converts the wavelength into HG light and obtains oscillation in the ultraviolet to blue wavelength band. As this SHG solid-state laser, a high-output pumped semiconductor laser can be used, so that an output of 10 mW to 300 mW is obtained. Further, similarly to the bulk direct conversion SHG laser, noise due to instability due to return light does not occur.

Alternatively, as shown in FIG. 2C, a structure in which the wavelength is locked and the wavelength can be tuned (distributed Bragg DBR: Distributed Bragg Reflector, distributed feedback D
Off-cut Mg with FB (distributed feedback)
A semiconductor laser produced by O-LiNbO3 (see Japanese Patent Application Laid-Open No. 9-218431) is used as the pumping semiconductor laser 120, and the wavelength of the pumping semiconductor laser 120 is 800 to 100.
When the output is 100 to 200 mW at 0 nm, the wavelength 400
A waveguide-type SHG laser capable of obtaining SHG light of several tens of mW at up to 500 nm can also be used. This waveguide type SHG laser has a waveguide period inversion domain SHG1.
Since the oscillation wavelength can be adjusted to 21 phase matching wavelengths, SH
Since the G efficiency can be adjusted to the maximum value and, as a result, the amount of output light can be maximized, a light source with high power can be configured.

On the other hand, the reading light optical system 90 used in the first embodiment has a long reflecting mirror 96 and a cylindrical lens 95 as shown in FIG. The long-type reflection mirror 96 includes the elements 16a and 17
a in a plane parallel to the direction in which the detectors 30 are arranged and perpendicular to the surface of the detector 30 so that the reflection surface 96a faces the surface of the detector 30 at a predetermined angle to the surface. ing. The cylindrical lens 95 is arranged between the long reflective mirror 96 and the detector 30 so that the generatrix is in the same direction as the arrangement direction of the elements 16a and 17a. The laser light source 81 and the long reflecting mirror 9
6, the light beam P emitted from the laser light source 81
May be provided with a collimator lens (not shown) for converting the light into a substantially parallel light flux and entering the long reflection mirror 96.

On the reflection surface 96a of the long reflection mirror 96, as shown in an enlarged view of FIG. 3B, a large number of minute convex surfaces 98 are linearly arranged in the length direction. The axial direction of the minute convex surface 98 is the element 16, 1
It may be a convex cylindrical surface formed so as to be parallel to 7a, or a convex spherical surface. Small convex surface 9
The curvature of 8 is set to a value such that the light beam P reflected by the minute convex surface 98 passes through the cylindrical lens 95 and enters the detector 30.

The reading light optical system 90 according to the first embodiment has a very compact structure as compared with a reading light optical system 90 (see FIG. 4) according to a second embodiment described later. .

The reading light irradiation means 80 includes a laser light source 81 and a reading light optical system 90 integrated with the element 16.
A moving (scanning) means (not shown) for mechanically moving (mechanical scanning) relatively in the longitudinal direction of a and 17a is provided. As a result, as shown in FIG. 1, the reading light irradiating means 80 makes the reading light L2 converged in a line shape substantially orthogonal to the elements 16a and 17a, and
Longitudinal direction of 6a, 17a (arrow Y direction in FIG. 1A)
Is configured to perform scanning exposure. The scanning exposure with the reading light L2 corresponds to sub-scanning.

The reading light optical system 9 constructed as described above
0, the light beam P is emitted from the side face of the detector 30 to the long reflective mirror 96 so that the optical axis of the light beam P emitted from the laser light source 81 is the same as the direction in which the elements 16 and 17a are arranged. When the light beam P is incident on the reflection surface 96a, the light beam P is reflected at the minute convex surface 98 at a predetermined divergent angle to the detector 30 side, so that the light beam P expands in the direction in which the elements 16 and 17a are arranged. The light enters the cylindrical lens 95.

When the convex cylindrical surface is used as the minute convex surface 98, the light beam P is applied to the elements 16, 1
Although the light beam P hardly spreads in the length direction of the element 7a, when the convex spherical surface is used as the minute convex surface 98, the light beam P slightly spreads in the length direction of the elements 16, 17a.

As described above, since the cylindrical lens 95 is arranged so that its generatrix is in the same direction as the arrangement direction of the elements 16a and 17a, the light beam P incident on the cylindrical lens 95 is at least In the direction in which the elements 16a and 17a are arranged, the light beam P reflected by the minute convex surface 98 passes through the cylindrical lens 95 and enters the detector 30 while maintaining the spread angle formed by the light beam P. Accordingly, the light beam P expanded in the direction in which the elements 16 and 17a are arranged by the long reflective mirror 96 is maintained in the expanded state at least in the direction in which the elements 16a and 17a are arranged.

On the other hand, since the cylindrical lens 95 is arranged so that its generatrix is in the same direction as the arrangement direction of the elements 16a and 17a, the elements 16a and 17a are arranged.
The light beam P converges on the detector 30 in the length direction of a (that is, the sub-scanning direction). As a result, on the detector 30, a linear light beam P that is enlarged in the direction in which the elements 16a and 17a are arranged and converged in the sub-scanning direction is formed.

As a result, the light beam P emitted from the laser light source 81 has almost all the light beams incident on the detector 30 in a linear manner, so that the light use efficiency is improved.
In addition, since the cylindrical lens 95 is used, the light beam P is converged in the sub-scanning direction regardless of whether the convex cylindrical surface is used as the minute convex surface 98 or the convex spherical surface is used. Is easy.

Note that the light beam P formed in a line is
Actually has an elliptical shape extending in the direction in which the elements 16a and 17a are arranged as shown in FIG. 3C2, and has an intensity distribution as shown in FIG. 3C3.

On the other hand, as shown in FIG.
The current detection circuit 70 is connected to a. The current detection circuit 70 reads out the charge corresponding to the latent image charge stored in the power storage unit in the detector 30 for each element 17a, and outputs an image signal having a level corresponding to the amount of the latent image charge. This is detected for each element 17a. The configuration of the current detection circuit 70 may be any configuration as long as an image signal of a level corresponding to the amount of latent image charge stored in the power storage unit can be obtained (for example, the applicant of the present application). Japanese Patent Application Nos. 10-232824 and 10-27
No. 1374).

The current detecting circuit 70 includes an element 17a
A current detection amplifier 71 to which an image signal S is input every time and a correction unit 74 for reducing unevenness of an image due to the intensity distribution of the reading light L2 are provided. The correction means 74 includes
A memory 75 for temporarily storing the image data output from the current detection amplifier 71, and a memory 76 for storing the correction data
Then, referring to the correction data D1 stored in the memory 76, the image data D0 read from the memory 75 is corrected for the unevenness of the image caused by the intensity distribution of the light beam P shown in FIG. Arithmetic means 77 for performing processing is provided.

When reading the image information from the solid-state radiation detector 30 in which the radiation image information is recorded as an electrostatic latent image by using the reading light irradiation means 80 configured as described above, the radiation solid-state detector 30 is used. 30 and the laser light source 81
A light beam P is emitted, and the reading light optical system 90 forms the light beam P as a linear reading light L2 as described above, and irradiates the detector 30 with the laser light source 81 and the reading light optical system. 90 is moved relatively to the detector 30 in the longitudinal direction of the elements 16a and 17a (the Y direction in FIG. 1A).

As a result, a current corresponding to the latent image charge flows out of the detector 30, and the current detection circuit 70 detects the current simultaneously for each element 17a to generate an image signal representing the electrostatic latent image. Obtain, that is, read the radiation image information.

By the way, when the light beam P emitted from the laser light source 81 is formed in a line on the detector 30, the intensity distribution is, as shown in FIG. 3C, the arrangement direction of the elements 16a and 17a. At X2, both ends of the detector 30 are weak and the center is strong.

The level of the image signal detected by the current detection circuit 70 depends on the intensity of the reading light L2.
An image signal having a distribution substantially similar to the intensity distribution of L2 is detected. That is, each element 1
As the image signal detected for each 7a, the signal level of the elements 17a arranged at both ends of the detector 30 is small, and the element 1 arranged at the center of the detector 30
The signal level for 7a increases. Therefore,
When an image is reproduced as it is based on an image signal obtained by scanning the entire surface of the detector 30 with the reading light L2, unevenness of the image having a distribution substantially similar to the intensity distribution occurs.

On the other hand, in the present embodiment, as shown in FIG. 1, a correction means 74 is provided so as to reduce the unevenness of the image caused by the intensity distribution. The memory 76 constituting the correction means 74 stores correction data for reducing unevenness of the image caused by the intensity distribution. The correction data is prepared for each element 17a. The calculating means 77 is provided in the memory 7
6 using the correction data D1 read from the memory 75 so that image unevenness due to the intensity distribution is reduced.
Correction data D1 for the image data D0 read from
Is performed. Thereby, when an image is reproduced based on the corrected image data D2, the problem of image unevenness due to the intensity distribution can be reduced.

As the correction data, the information of the intensity distribution itself may be stored, and the calculating means 77 may perform a correction operation to reduce the influence of the intensity distribution.

Also, the correction data is not prepared for each element 17a, but for each element 17a.
, Only the correction data may be prepared, and at the time of the correction calculation by the calculation means 77, the interpolation calculation may be performed for the element 17a for which no correction data is prepared.

The unevenness of the intensity distribution is reduced by changing the arrangement density of the convex surface between the center and both ends, or by changing the curvature of the convex surface between the center and both ends, so that the correction calculation is not performed. Also, image unevenness can be reduced.

Next, an image information reading apparatus according to a second embodiment of the present invention will be described.

FIG. 4 is a diagram showing a schematic configuration of an image information reading apparatus according to a second embodiment of the present invention. FIG. 4 is a sectional view (A) showing a line-shaped reading light in the width direction, and FIG. It is sectional drawing (B) which showed reading light in the length direction, and figure (C) which showed linear reading light.

The image information reading apparatus 1 according to the second embodiment has the same current detection circuit 70 as that used in the first embodiment, but the reading light irradiating means 8
0 is the image information reading apparatus 1 according to the first embodiment described above.
Is different from that used in Radiation solid state detector 30
Is a device in which the device unit 10 is laminated on the upper surface 20 a of the glass substrate 20.
0 on the upper surface 20a side as in the case of the solid-state radiation detector 30 used in the first embodiment described above.
An electrode layer is provided in which a number of elements 16a, 17a (not shown) are alternately arranged in a stripe shape such that the middle Y direction is the longitudinal direction.

The reading light irradiating means 80 used in the image information reading apparatus 1 according to the second embodiment is, as shown in FIG. 4, a laser light source 81 for emitting a light beam P and a laser light source 81 for emitting a light beam P. Reading light optical system 9 for irradiating light beam P to radiation solid state detector 30 as an image detector
0.

As the laser light source 81, a laser light source having a semiconductor laser or a laser-diode-pumped solid-state laser is used similarly to the laser light source used in the first embodiment.

The reading light optical system 90 condenses the light beam P emitted from the laser light source 81 between the laser light source 81 and the glass substrate 20 side of the radiation solid state detector 30 in order from the laser light source 81 side. A convex lens 91, a half mirror 92 that reflects a part of the light beam P toward the detection surface of the photodiode 88 and transmits the rest, and a slit plate 93 provided with a pinhole or a slit for passing the collected light beam P , A convex lens 94 for controlling the spread width of the light beam P passing through the slit plate 93 to a predetermined size, and a cylindrical lens 95 arranged so that the generatrix is in the same direction as the arrangement direction of the elements 16a. As the convex lenses 91 and 94, the light beam P is once converged on a pinhole or a slit portion of the slit plate 93, and then the cylindrical lens 95 has a predetermined divergence angle.
Further, the spread width of the light beam P is controlled so that the light beam P enters at a predetermined width within at least the axial width of the cylindrical lens 95.

Thus, when the light beam P is emitted from the laser light source 81 at a predetermined divergence angle, the light beam P is converged once and passes through a pinhole or a slit (spatial filtering). Laser light source 8
A natural light component (a flare component that cannot be stopped down on the focus surface) included in the light beam P emitted from 1 is cut off.

Further, as described above, since the cylindrical lens 95 is arranged so that its generatrix is in the same direction as the arrangement direction of the elements 16a, the light beam P incident on the cylindrical lens 95 can emit at least the element 16a. In the arrangement direction, the light enters the detector 30 through the cylindrical lens 95 while maintaining the divergence angle of the control lens 91. Thereby, the laser light source 81
The light beam P emitted from the
6a is enlarged in the arrangement direction.

On the other hand, since the cylindrical lens 95 is arranged so that its generatrix is in the same direction as the arrangement direction of the elements 16a, the light beam P is transmitted in the length direction of the element 16a (same as the sub-scanning direction). Detector 30
Converges on As a result, on the detector 30 device, a linear light beam P that is enlarged in the arrangement direction of the elements 16a and converged in the sub-scanning direction is formed.

Thus, the light beam P emitted from the laser light source 81 is such that almost all of the light flux enters the lower surface 20 b of the glass substrate 20 of the detector 30 and then enters the device section 10 in a linear manner. Therefore, light use efficiency is improved. Further, since the cylindrical lens 95 is used, it is easy to converge the light beam P in the sub-scanning direction. Further, since a semiconductor laser is used as a light source, it is possible to secure sufficient light intensity with a small amount of power.

The beam shape of the light beam P converged in a line on the device section 10 in this manner is shown in FIG.
As shown in the figure, the length X2 is substantially equal to the arrangement width X1 of the elements 16a of the device section 10, and the width X3 is equal to the resolvable pixel size in the sub-scanning direction at the time of reading, or It is desirable that the scanning pitch be equal to or less than the scanning pitch (in the direction of arrow Y in FIG. 1A). The light beam P thus formed in a line is used as the reading light L2.

The reading light irradiating means 80 integrally includes a laser light source 81 and a reading light optical system 90 as shown in FIG.
A mechanical moving (scanning) means (not shown) for relatively moving (mechanical scanning) in the direction is provided. As a result, the reading light irradiating means 80 applies the reading light L2 converged in a line shape to the direction of the arrow Y in FIG. 4A (similar to the first embodiment, the elements 16a and 17a not shown). While being substantially perpendicular to the longitudinal direction, the elements 16a, 17
(longitudinal direction a).
The scanning exposure using the reading light L2 also corresponds to the sub-scanning.

The method of reading image information from the solid-state radiation detector 30 on which radiation image information is recorded as an electrostatic latent image by using the reading light irradiation means 80 according to the second embodiment configured as described above is as follows. This is the same as the case where the reading light irradiation means 80 according to the first embodiment is used.

In the case where the reading light irradiating means 80 according to the second embodiment is used, the light beam P formed in a line shape as shown in FIG. Although it has an intensity distribution, by performing correction processing in the same manner as in the first embodiment, image unevenness due to the intensity distribution can be reduced.

Although the preferred embodiments of the image information reading method and apparatus according to the present invention have been described above, the present invention is not necessarily limited to the above-described embodiments.

For example, the above description has been made on the case where the solid-state radiation detector is used as the image detector. However, the image detector is not limited to the solid-state radiation detector, and the image information is not limited to the solid-state radiation detector. And a plurality of linear electrodes for extracting electric signals of a level corresponding to the amount of the latent image charges stored in the two-dimensionally-stored charge storing the electric charges carrying as the latent image charges. Any optical reading type image detector may be used. For example, it may be composed of only stripe electrodes without sub-electrodes.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an image information reading device according to a first embodiment of the present invention;

FIG. 2 is a diagram illustrating an example of a laser diode-pumped solid-state laser.

FIG. 3 is a view showing details of a reading light irradiation unit used in the image information reading apparatus shown in FIG. 1, and is a front view (A), a left side view (B), and a front view showing a light beam intensity distribution. (A)
(C1) to (C3) shown corresponding to FIG.

FIG. 4 is a diagram showing a schematic configuration of an image information reading apparatus according to a second embodiment of the present invention, and is a sectional view (A) showing a line-shaped reading light in a width direction and a line-shaped reading light. (B) in a longitudinal direction, and (C) in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image information reading apparatus 10 Device part 20 Glass substrate 20a Upper surface 20b Lower surface 30 Solid-state radiation detector as an image detector 70 Current detection circuit 74 Correction means 80 Reading light irradiation means 90 Reading light optical system 96 Elongated reflection mirror 98 Micro convex

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01S 5/02 H01S 5/02 H04N 1/04 H04N 1/04 EF term (Reference) 2H013 AC01 AC05 2H045 AG09 5C072 AA01 BA06 BA17 CA06 DA03 DA04 HA02 HB10 RA12 VA01 5F072 AB02 KK12 MM08 QQ02 RR03 YY15 5F073 AB23 AB27 BA04 EA07 EA15 EA27

Claims (9)

[Claims] 1. A two-dimensionally distributed power storage unit for storing charges carrying image information as latent image charges, and an electric signal of a level corresponding to the amount of the latent image charges stored in the power storage unit is taken out. Using a light reading type image detector in which a large number of linear electrodes are arranged substantially parallel to each other, a linear read light extending in the direction in which the linear electrodes are arranged is transmitted in the longitudinal direction of the linear electrodes. Scanning, and acquiring the electric signal output for each of the linear electrodes by the scanning, thereby reading the image information from the image detector in which the image information is recorded as an electrostatic latent image in the power storage unit. In the image information reading method, the light beam is expanded in the direction in which the linear electrodes are arranged and converged in the scanning direction to form the linear reading light. 2. An elongated reflecting mirror having a large number of minute convex surfaces arranged in a straight line, wherein said minute reflecting mirror is arranged in a plane parallel to a direction in which said linear electrodes are arranged and perpendicular to a surface of said image detector. The light beam is disposed in such a manner that the convex surface faces the surface and forms a predetermined angle with respect to the surface, and the light beam is elongated so that the optical axis of the light beam is the same as the arrangement direction. 2. The image information reading method according to claim 1, wherein the light beam is expanded in a direction in which the linear electrodes are arranged by making the light beam incident on a reflection mirror and reflecting the light beam on the minute convex surface. 3. The cylindrical optical member is arranged such that the generatrix of the cylindrical optical member is in the same direction as the direction in which the linear electrodes are arranged, and the light beam expanded in the direction in which the linear electrodes are arranged is subjected to the cylindrical optical member. 3. The image information reading method according to claim 1, wherein the line-shaped reading light is formed by being incident on a member. 4. The apparatus according to claim 1, wherein the unevenness of the read image information due to the intensity distribution of the linear read light in the direction in which the linear electrodes are arranged is corrected.
The image information reading method according to claim 1. 5. A two-dimensionally distributed power storage unit for storing charges carrying image information as latent image charges, and extracting an electric signal at a level corresponding to the amount of the latent image charges stored in the power storage unit. An image sensor of an optical reading system in which a large number of linear electrodes are arranged substantially in parallel, and a linear read light extending in the direction in which the linear electrodes are arranged is scanned in the longitudinal direction of the linear electrodes. An image information reading apparatus comprising: a reading light irradiation unit that irradiates substantially the entire surface of the image detector; and an image signal obtaining unit that obtains an electric signal output for each of the linear electrodes by the scanning. The irradiating means includes an optical system for expanding the light beam in the direction in which the linear electrodes are arranged and converging the light beam in the scanning direction to form the linear read light. Image information reading device. 6. The optical system according to claim 1, wherein the plurality of minute convex surfaces are linearly arranged, and the minute convex surface is formed in a plane parallel to a direction in which the linear electrodes are arranged and perpendicular to a surface of the image detector. Comprises a long reflecting mirror arranged at a predetermined angle to the surface so as to face the surface, and the long reflecting mirror is arranged so that the optical axis is the same as the alignment direction. 6. The image information reading apparatus according to claim 5, wherein the light beam is expanded in the direction in which the linear electrodes are arranged by reflecting the light beam incident on the reflection mirror on the minute convex surface. 7. The optical system is arranged such that a generatrix is arranged in the same direction as the arrangement of the linear electrodes, and forms an incident light beam expanded in the arrangement direction of the linear electrodes into the line. 7. The image information reading device according to claim 5, wherein the image information reading device has a cylindrical optical member. 8. The apparatus according to claim 5, wherein said reading light irradiating means includes a semiconductor laser or a laser diode pumped solid-state laser for emitting said light beam.
8. The image information reading device according to any one of claims 1 to 7. 9. A correcting means for correcting unevenness of the image information carried by the electric signal acquired by the image signal acquiring means, which is caused by the intensity distribution of the linear reading light in the direction in which the linear electrodes are arranged. 9. The image information reading apparatus according to claim 5, further comprising: