JPS61239211A - Optical beam scanner incorporating light source - Google Patents

Abstract

PURPOSE:To make a device small-sized and to make the optical axis adjustment easy by turning or shaking one cylinder body, which incorporates a light source generating an optical beam and an optical system shaping the section of the optical beam, to turn the optical beam and scanning the optical beam thereby. CONSTITUTION:A vertical cylinder body 1 is connected to a motor 2 by a shaft 3 and is turned in the direction of an arrow. A light source 4 like a semiconductor laser is provided in the lower part of the cylinder body 1 and projects the optical beam upward along the axis. The current modulated by a picture signal is supplied through slip rings 5 and 6 and feeding sliders 7 and 8 provided on the outside of the cylinder body 1 to adjust the luminance of the light source 4. The optical beam from the light source 4 is shaped by lenses 9 and 10 to become parallel rays of light and is reflected by a prism 11 stuck to the end part of the cylinder body 1 and is scanned horizontally on the surface of photosensitive materials 13 through an f.theta lens 12. Thus, the adjusting work of the optical axis for assembling is made unnecessary and the device is made small- sized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides an optical system that uses a light beam modulated by an image signal to
Regarding a light beam scanning device that records a duplicate image by sweeping the surface of a photosensitive material, in particular, a light source that generates a light beam and an optical system for shaping the cross-sectional shape of the light beam are built into one cylindrical body, The present invention relates to a light beam scanning device whose overall size is reduced by rotating or swinging the cylindrical body to rotate and scan the light beam.

[Prior Art] Conventionally, a method of deflecting a light beam using a rotating mirror as shown in FIG. 6 has generally been applied to a light beam scanning device. That is, a light beam projected from a light source (61) such as a laser is modulated as required by a light modulation element (62) controlled by a single image signal (S), and an appropriate beam expander, collimator optical system, etc. (63), it is projected onto the surface of a polygon mirror (64) which is rotationally driven by a motor (65).
4) The light beam reflected by the rotation of the f/θ lens (
The photosensitive material (67) is scanned and exposed through the photosensitive material (66) to record a duplicate image.

[Problems to be Solved by the Invention] In the above-mentioned conventional device, optical elements such as a light modulation element and various lens systems, and light deflection means such as a polygon mirror are arranged independently along the optical axis. If these elements are not precisely aligned to the optical axis, the cross-sectional shape of the light beam,
That is, problems such as deformation of the shape of the light spot projected onto the surface of the photosensitive material and occurrence of flare occur. Therefore, when manufacturing such a light beam scanning device, adjustment work is required to align these optical elements with the optical axis.
This means aligning a large number of optical elements to the optical axis one by one. For example, if the position or attitude of the optical deflection means is changed, the light source, multiple lenses, etc. will be aligned one by one in the space. It takes a lot of effort to readjust the three axes, and each optical element is relatively small and inconvenient to handle, so precise work based on a high level of skill is required.

It tends to be inefficient and becomes a bottleneck in production.

Also, the rotating polygon mirror that deflects the light beam is
In order to make the scanning state of the light beam constant for each reflecting surface, it is necessary that each reflecting surface is formed into an accurate regular polygonal shape and that there is no variation in the reflection direction of each surface, that is, there is no so-called tilting of the surface. Therefore, manufacturing polygon mirrors requires highly precise processing technology and has a low production yield rate, which often presents a bottleneck.

The present invention is intended to solve the inconveniences in the prior art.

[Means for solving the problem] A cylindrical body that rotates or swings around the optical axis of the light beam projected from the light source is provided, and the cylindrical body has a
A light source and optical elements such as a beam expander and a collimator optical system are each fixedly built in, and a light beam shaped as desired by these optical elements is transmitted to a rectangular prism or a flat mirror attached to a cylindrical body. The light is bent in a desired direction with respect to the axis of the cylinder by a reflecting means and projected onto the surface of the photosensitive material to be scanned, and the cylinder is rotated or swung.

The photosensitive material is scanned and exposed.

[Function] The light source, the light beam shaping optical system, and the light beam reflecting means are integrated into a cylinder that rotates or swings, so that each optical element is aligned in the direction along the axis of the cylinder. Because it has only one degree of freedom, each element can be easily aligned to the optical axis, and only these optical elements can be assembled and adjusted as an independent unit separate from the main body of the scanning device. This makes it possible to streamline the production process.

In addition, since it is configured as a single unit, for example, when adjusting the scanning exposure position on the surface of the photosensitive material,
When the position or attitude of the reflecting means is changed, the other optical elements move while maintaining their relative positions with the reflecting means, thereby eliminating the need for readjustment work for each individual element.

[Embodiment] FIG. 1 is a partially cutaway perspective view showing one embodiment of the present invention. The vertical cylinder (1) is connected to the motor (2) below it.
) is connected by a shaft (3) and rotates around the central axis.

Inside the cylindrical body (1), a light source (4) such as a semiconductor laser is installed at the bottom, and projects a light beam upward along the central axis of the cylindrical body (1). The light source (4) is supplied with a required image signal via ring-shaped power receivers (5) (6) and power feed sliders (7) (8) attached to appropriate locations on the outer surface of the cylindrical body (1). A modulated current is supplied.

Flash the light beam at the required timing.

The light beam projected from the light source (4) is transmitted through the columnar lens (9
), its cross-sectional shape is shaped, and then the collimator lens (10) converts it into a parallel light beam, which is then sent to the cylindrical body (1
) and is emitted in the horizontal direction. The right angle prism (11) is fixedly installed in the cylinder body (1), so the prism (11)
The light beam emitted horizontally from the cylinder (1)
The photosensitive material (13) is rotated around the cylindrical body (1) as the center of rotation is rotated, and the surface of the photosensitive material (13) placed facing the center of rotation is scanned in the horizontal direction via the f/θ lens (12). do.

In the device of the first illustrated embodiment, the light source (4), the optical system (9), (10) for beam shaping, etc. are arranged with the central axis of the cylinder (1) as a reference, so it is difficult to attach each component during assembly. It is easy to determine the position, and since each part is fixed inside the cylinder (1), there is an advantage that no displacement occurs during use.

Next, FIG. 2 is a perspective view showing the main parts of an apparatus according to another embodiment of the present invention, showing the inside and upper half of the cylindrical body (1).

Since it is the same as the first illustrated device, illustration and description will be omitted.

The second illustrated device is the motor (2) in the first illustrated device.
Instead, a galvanometer (14) is used to reciprocate the cylindrical body (1) within a required angle range.

Therefore, power is supplied to the light source (4) by extending and contracting the power cord (15) (16) connected to the appropriate position of the cylinder (1).
), it is not necessarily necessary to provide complicated means such as the annular power receiving body (5) (6) of the first illustrated device and the power feeding slider (7) (8), and the slider It is possible to prevent disturbance of the light beam due to the jump of the light beam and separation from the surface of the power receiver, and the resulting noise generated in the recorded image.

In addition, in the first illustrated apparatus, since the light beam continuously rotates in one direction, the photosensitive material (1
3) It is necessary to scan to areas other than 5.
However, the second illustrated device can scan only the required range by appropriately adjusting the swing angle range, and the above-mentioned drawback can be solved.

Next, FIGS. 3 to 5 are partially cutaway elevational views showing one embodiment of the optical beam shaping optical system built into the cylinder (1), respectively.

FIG. 3 shows the same device as the one shown in FIG.
), motor (2), light source (4), annular power receiver (5) and (6), power feed slider (7) and (8), columnar lens (
9), collimator lens (10), right angle prism (11)
). These have already been explained with reference to FIG.

In Fig. 4, the lens and right-angle prism are the same as those shown in Fig. 3, but the light source (17) is attached to a window hole provided in the side wall of the cylindrical body facing inward, and a mirror is tilted inside the cylindrical body. (18)
This allows the light beam to be reflected in the direction along the central axis of the cylinder. Thereby, the light source (17) can be easily replaced.

The device shown in FIG. 5 has almost the same configuration as the device shown in FIG. ) is used.

In each of the above-mentioned embodiments, the light beam emitted in the vertical direction is refracted in the horizontal direction.

In both cases, a right-angled prism is used, but other means may be used.

For example, the present invention can be practiced even if a plane mirror is fixedly installed at the upper end of the cylindrical body (1) at an angle of 45 degrees.

These prisms or plane mirrors do not necessarily reflect the light beam in a direction perpendicular to the axis of rotation of the cylinder, but in that case, in practical terms, the scanning locus of the light beam on the surface of the photosensitive material is It is desirable to take measures such as placing an auxiliary optical system such as a prism in front of the f/θ lens, for example, so that the angle becomes linear.

Furthermore, in the above description, the cylinder body (1) is held vertically, and the scanning light beam is rotated in a horizontal plane to perform scanning. However, the cylinder body (1) is not necessarily limited to this. ) may be rotated around a horizontal axis to scan and expose the photosensitive material traveling in the horizontal direction, or it may be installed in any orientation, not limited to the horizontal or vertical direction, to perform scanning exposure. is possible.

Furthermore, in each of the embodiments described above, the light beam from the light source is converted into parallel light by a collimator lens or the like.

Although the light beam is projected onto the surface of the photosensitive material through a reflection means, once the light beam is focused on the reflection surface or a position in front of or behind it,
The light may be focused again on the surface of the photosensitive material.

In each of the above-mentioned embodiments, the shaft support means for the rotating or swinging cylinder are omitted from illustration or explanation because conventional techniques can be applied; In order to prevent vibration, it is desirable to support both ends of the cylindrical body with appropriate bearings or the like. To achieve this, the cylinders (1) of the first to fifth illustrated devices may be extended above the right-angled prism (11) to form shaft portions at both ends, and each may be supported by a bearing.

[Effects of the Invention (1) Since the light source and optical beam shaping optical system in the light beam scanning device are combined into an integrated unit, optical axis adjustment during device assembly, which conventionally required considerable effort, is now possible. This eliminates the need for labor and streamlines production.

(2) The light source and the light beam shaping optical system are compactly housed inside the relatively small cylinder, and these parts are fixed to the cylinder, making manufacturing and maintenance easy. be.

(3) Since the light source and the optical system are made compact, the entire device becomes compact, which contributes to resource saving, and it is possible to realize a device that is advantageous in terms of equipment cost, space, etc.

(4) Since the traveling posture of the photosensitive material to be scanned and the corresponding posture of the cylinder can be arbitrarily selected as necessary, it can be applied to various types of light beam scanning devices; Has wide versatility.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a schematic configuration of a device according to one embodiment of the present invention, FIG. 2 is a perspective view showing main parts of another embodiment of the device, and FIG.
5 through 5 are sectional views showing one embodiment of the optical system inside the cylinder, and FIG. 6 is a perspective view showing the configuration of a conventional light beam scanning device. (1)...Cylinder, (2)...Motor, (4)...
・Light source, (5) (6)... Annular power receiving body, (7) (8
)...Feed slider, (9)...Column lens, (io
)...Collimator lens, (11)...Right angle prism, (11')...Special prism. (12)...f/theta lens, (13)...photosensitive material, (14)...galvanometer, (15) (16)
)...Power supply cord, (17)...Light source, (18)...
...Reflector, (61)...Laser light source, (62)...Light modulation element, (63)...Optical system for light beam shaping, (64)...
... Polygon mirror, (65) ... Motor, (6
6)...Photosensitive material. More than that / Ii

Claims (7)

[Claims] (1) a cylindrical body that rotates or swings around a central axis; a light source built into the cylindrical body that projects a light beam along the central axis; and a light source that projects a light beam along the central axis; an optical system built into the cylindrical body; a light beam reflecting means fixed to the cylindrical body so as to reflect the projected direction of the shaped light beam in a desired direction with respect to the central axis; and the cylindrical body. A light beam scanning device with a built-in light source and a drive means for rotating or swinging around a central axis. (2) A ring-shaped power receiving body is attached to the appropriate position of the rotating cylinder,
A light beam scanning device incorporating a light source according to claim 1, wherein power is supplied to the light source via a slider that slides into contact with the power receiving body. (3) The light source is supplied with power by a flexible electric wire connected to an appropriate position of the swinging cylinder.
A light beam scanning device incorporating the light source described in item 1). (4) A light beam scanning device with a built-in light source as set forth in claim (1), wherein the light source is a semiconductor laser, and the light source is blink-controlled by an image signal to record a duplicate image by exposure. Device. (5) A light beam scanning device incorporating a light source according to claim (1), wherein the optical system includes a columnar lens and a collimator lens. (6) A light beam scanning device incorporating a light source according to claim (1), wherein the light beam reflecting means is a right-angle prism. (7) A light beam scanning device incorporating a light source according to claim (1), wherein the light beam reflecting means is a plane mirror tilted at 45 degrees with respect to the optical axis.