JPS63259616A - Light beam scanning and recording device - Google Patents

Abstract

PURPOSE:To simplify an optical system, and to prevent fog from being generated due to a synchronizing light beam, by using the synchronizing light beam whose wavelength is outside of a photosensitive wavelength area of a recording body. CONSTITUTION:The titled recorder is provided with a synchronizing light source 2 for generating a synchronizing light beam 2A having wavelength being outside of a photosensitive wavelength area of a recording body to which a recording light beam 1A executes a scan two-dimensionally, a light beam synthesizing element 4, a light beam splitting element 8, and a photodetector 12 for detecting the synchronizing light beam which has passed through a grid 10. In such a state, the recording light beam 1A and the synchronizing light beam 2A are synthesized at this side of an optical deflector 6, and split suitably after they are deflected. Accordingly, a part or all of optical elements to which it is required that both light beams pass through placed on an optical path on which both the beams are synthesized, and they can be used in common to both the beam. Also, even if a part of the synchronizing light beam 2A is made incident on a recording body together with the recording light beam 1A by this split, the wavelength of the synchronizing light beam 2A is outside of the photosensitive wavelength area of the recording body, and the recording body is not sensitized. In such a way, the generation of fog is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a light beam scanning recording device that records an image by deflecting a recording light beam modulated based on image information to scan over a recording medium. In particular, the present invention relates to a light beam scanning recording device capable of obtaining the above-mentioned scanning synchronization signal.

(Prior Art) Conventionally, a recording light beam emitted from a recording beam light source is modulated based on image information, and the modulated recording light beam is deflected by an optical deflector to produce a two-dimensional image on a recording medium. Various light beam scanning and recording apparatuses have been proposed that record image information on a recording medium by scanning the recording medium. These light beam scanning recording devices, for example, have been proposed by the applicant in recent years and are attracting attention, and they scan a stimulable phosphor sheet on which emitted Tmm image information is stored and recorded with excitation light, thereby producing an emitted 131alI image. It is connected to a radiation image information reading device that photoelectrically reads information and outputs an image signal, and is suitably used to obtain a hard copy of high quality that is suitable for image interpretation based on the obtained image signal. .

Further, as the recording device, there is also one in which a synchronization light beam is made incident on an optical deflector that deflects the recording light beam, and the deflected synchronization light beam is made incident on a grid to obtain a synchronization signal. Much known.

In the device described above that uses a synchronization light beam to obtain a synchronization signal, the recording light beam and the synchronization light beam are coaxially combined before entering the optical deflector, and after being deflected by the optical deflector, If these light beams are split again so that one scans the recording medium and the other scans the grid, the recording light beam and the $111 light beam will pass through a common optical element. This is preferable because the optical system is simplified. The above-mentioned synthesis of the recording light beam and the synchronization light beam into nine divisions can be easily carried out using a dichroic mirror if the wavelengths of the two light beams are made different from each other.

(Means for solving the problem) However, in this case, when the recording light beam and the synchronization light beam that have been coaxially combined and deflected are split again by the dichroic mirror, the synchronization light beam may not be completely split from the recording light beam, and part of the synchronization light beam may enter the recording medium together with the recording light beam. If the light is incident, fog will occur in the image recorded on the recording medium, making it impossible to obtain a highly accurate reproduced image.

Therefore, in conventional devices, the synchronization light beam and the recording light beam are not coaxially combined, but are made to enter the optical deflector from different directions. The optical paths of the light beams are set to be different from each other. In this case, although there is no risk of fogging caused by the synchronizing light beam as described above, a beam expander is required for both light beams.

Since optical elements such as lenses are required, there are problems in that the configuration of the device becomes complicated and large, and the manufacturing cost increases.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a light beam scanning recording device that can simplify the optical system and does not cause fogging due to the synchronization light beam. That is.

(Means for solving the problem) The light beam scanning recording device of the present invention has two recording light beams.
A synchronization light source that emits a synchronization light beam having a wavelength outside the photosensitive wavelength range of the recording medium that is dimensionally scanned; the synchronization light beam emitted from this synchronization light source is converted into a recording light beam before an optical deflector. a light beam combining element for combining the two light beams, and a light beam provided on the optical path of the recording light beam and the synchronization light beam reflected and deflected by the optical deflector, and splitting both light beams and guiding the scanning light beam to the recording medium. Beam splitting element, grid provided on the optical path of the split synchronization light beam,
and a light detection means provided behind the grid to detect the synchronization light beam passing through the grid.

(Function) In the above device, the recording light beam and the synchronization light beam are combined before the optical deflector, and are split appropriately after deflection. Alternatively, they can all be placed on the optical path where both beams are combined and used in common for both beams. Furthermore, even if a part of the synchronization light beam enters the recording medium together with the recording light beam due to the above division, the wavelength of the synchronization light beam is outside the photosensitive wavelength range of the recording medium, and the recording medium will not be exposed to light. Therefore, there is no risk of fogging.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a light beam scanning recording device according to an embodiment of the present invention.

The equipment shown includes external images &! A first semiconductor laser 1, which is a recording beam light source, is directly modulated in analog form by a modulation circuit 3 based on an image signal obtained from an a-taking device;
and a second semiconductor laser 2 which is a synchronizing beam light source that is always driven in a constant state, and the first semiconductor laser has a wavelength 78 which is modulated according to the image signal.
The second semiconductor laser 2 emits a recording light beam 1A of 0na+ and a synchronization light beam 2Δ with a wavelength of 1.5μ and a constant intensity. The dichroic mirror 4 enters the first dichroic mirror 4, which is a light beam combining element, which transmits the light having the wavelength of the synchronizing light beam 1A and reflects the light having the wavelength of the synchronizing light beam 2A. It is combined into beam 3Δ.

This combined beam 3A passes through a double expander 5 and is expanded to a desired beam diameter, and then enters a rotating polygon mirror 6 that rotates in the six directions of arrows and is reflected and deflected. The reflected and deflected combined beam 3A passes through a scanning lens 7 such as a θ lens, and then becomes a light beam that reflects the light with the wavelength of the recording light beam 1Δ and transmits the light with the wavelength of the synchronization light beam 2Δ. The light enters the second dichroic mirror 8, which is a splitting element, and is split again into a recording light beam 1A and a synchronization light beam 2A. A recording sheet 9, which is a recording medium, is arranged below the second dichroic mirror 8, and this recording sheet 9 is conveyed in the direction of arrow B at a constant speed. The recording light beam 1A reflected by the second dichroic mirror 8 repeatedly scans the recording sheet 9 in the direction of arrow A', which is substantially perpendicular to the direction of arrow B, by deflection of the rotating polygon mirror described above. By the main scanning of this recording light beam 1A and the conveyance (sub-scanning) of the recording sheet 9, the recording sheet 9
is scanned by the recording light beam 1Δ over its entire surface, and image information is recorded. The recording light beam 1A deflected at a constant angular velocity by the rotating polygon mirror 6 is focused on the recording sheet 9 by the scanning lens 7 and scanned at a constant velocity. Further, the photosensitive wavelength range of the recording sheet 9 is, for example, 400 nm to 900 nIll.

On the other hand, the synchronizing light beam 2A transmitted through the second dichroic mirror 8 is arranged on the optical path, and the synchronizing light beam 2A is arranged on the optical path.
Grid 10 having a plurality of gratings extending in the scanning direction of Δ
incident on . The synchronizing light beam 2A that has passed through the grid 10 is directed to a condensing bar 1 provided behind the grid 10.
1, and the collected light is detected by photodetectors 12 provided at both ends of the focusing bar. The amount of light detected by the photodetector 12 changes with the main scanning of the recording light beam 1A due to the lattice of the grid 10. The photodetector 12 detects a synchronous change in the light intensity of the synchronizing light beam 2A, and this light intensity change is converted into an electrical pulse signal by a synchronization signal generating means (not shown).
A synchronization signal indicating the position of the recording laser beam 1A in the main scanning direction is obtained. Note that the light detection means for detecting the light passing through the grid is not limited to the one consisting of a condensing bar and a photodetector as described above; A container may also be provided directly behind the grid.

By the way, if the recording light beam 1A and the synchronization light beam 2A are not completely divided by the second dichroic ink mirror 8, the synchronization light beam 2A along with the recording light beam 1A will appear on the recording sheet 9. A part of it may be incident. However, the wavelength of the synchronizing light beam 2A in this device is 1.5 μm, and the recording sheet 9
Therefore, the recording sheet 9 is not exposed to the synchronizing light beam 2A and is substantially scanned only by the recording light beam 1A. Therefore, even if the light beam is not completely split by the second dichroic mirror 8, a good image without fog can always be obtained. Furthermore, this device has the advantage that by once combining the recording light beam 1A and the synchronization light beam 2A and using them, both light beams can share optical elements such as the beam expander 5 and the scanning lens 7. This apparatus has such advantages and is capable of recording images with high precision.

In addition to the dichroic mirror 8 described above, a general half mirror 18 as shown in FIG. 2 may be used as a light beam splitting element for splitting the combined recording light beam and synchronization light beam. good. In this case, since a part of the recording light beam is incident on the grid 10 together with the synchronization light beam, it is preferable that the photodetector 12 detects the modulated recording light beam. If not, a filter 19 may be provided between the half mirror 18 and the grid 10 to selectively cut only the light having the wavelength of the recording light beam.

(Effects of the Invention) As explained above, according to the light beam scanning recording device of the present invention, by using a synchronizing light beam whose wavelength is outside the photosensitive wavelength range of the recording medium, the optical element of the device Even if the synchronizing light beam and the recording light beam are once combined in order to reduce the number of synchronizing light beams and then divided after deflection, the recording medium will not be fogged by the synchronizing light beam.

Therefore, it is possible to reduce the size and cost of the apparatus, and it is also possible to always reproduce highly accurate reproduced images.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a light beam scanning recording apparatus according to one embodiment of the present invention, and FIG. 2 is a schematic diagram of the main parts of the apparatus according to another embodiment of the present invention. 1... First semiconductor laser 1Δ... Recording light beam 2... Second semiconductor laser 2A... Synchronization light beam 4... First dichroic mirror 6... Rotating polygon mirror

Claims (1)

[Scope of Claims] 1) A recording light beam emitted from a recording light source and modulated based on image information is reflected and deflected by an optical deflector to scan the recording medium in the main scanning direction; The image information is recorded by moving the recording light beam and the recording medium relatively in a sub-scanning direction substantially perpendicular to the main scanning direction to scan the recording light beam two-dimensionally over the recording body. In a light beam scanning recording device, a synchronization light source emits a synchronization light beam having a wavelength outside the photosensitive wavelength range of the recording medium, and a synchronization light beam emitted from the synchronization light source is directed in front of the optical deflector. A light beam combining element is provided on the optical path of the recording light beam and the synchronization light beam reflected and deflected by the optical deflector to combine the recording light beam into the recording light beam. A light beam splitting element that guides the beam to the recording medium, a grid provided on the optical path of the split synchronization light beam, and a photodetector provided behind the grid to detect the synchronization light beam that has passed through the grid. A light beam scanning recording device characterized by comprising: means. 2) The light beam scanning recording apparatus according to claim 1, wherein the light beam splitting element is a dichroic mirror.