JPH08184773A - Optical scanner - Google Patents

Abstract

PURPOSE: To eliminate the need for a reflection mirror supporting plate and to reduce the cost of a device by directly fixing reflection mirror to a chassis and position-adjustably mounting a substrate to be placed with a photodetector at this chassis. CONSTITUTION: A circuit board 1 is arranged on the lower side of the chassis 18 in such a manner that its front surface faces downward and a pin photodiode 17a is so positioned as to be held projected to the inner side of the chassis 18 from an opening bored at the chassis 18. The circuit board 1 is bored with a slot and the chassis 18 is projectingly provided with a pin to be loosely arranged in this slot. Then, the position of the pin photodiode 17a relative to the chassis 18 is adjusted by adjusting the relative position of the pin in the slot in the state of keeping a cover attached to the chassis 18, by which the timing of a synchronizing signal is adjusted. The circuit board 1 is fixed to the chassis 18 by a fastening means in the state that the timing adjustment of the synchronizing signal is completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device.

[0002]

2. Description of the Related Art Conventionally, there is known an optical scanning device for recording image information such as characters and figures on an image recording medium such as a photoconductor by deflecting a light beam and optically scanning the image information. FIG. 5 shows an example of this optical scanning device.

In the figure, reference numeral 11 indicates a semiconductor laser unit as a light beam generating means. The semiconductor laser unit 11 includes a laser chip and a collimator for collimating laser light emitted from the laser chip. It has a built-in lens. The parallel light emitted from the laser unit 11 is converged by the cylindrical lens 13a on the mirror surface of, for example, a rotating polygon mirror (polygon mirror) 12 as a polarization scanning means. This rotating polygon mirror 12
Is rotated by a rotary polygon mirror drive motor (not shown).

The converged laser light has a uniform linear motion in the main scanning direction through the fθ lens 13b, and pitch unevenness is corrected in the sub scanning direction. The laser light emitted from the fθ lens 13b is reflected by the fixed mirrors 14 and 15 and the timing adjusting mirror 16 as shown when it reaches a position immediately before the start end position of the image recording area of the image recording medium (not shown). The non-focused beam reflected by the timing adjusting mirror 16 is directed to, for example, a Pin photo (a kind of photodiode) 17a, which is a photoelectric conversion element forming a photodetector, and the position of the Pin photo 17a. At this point, it becomes a condensed beam and is received by the Pin photo 17a.

The Pin photo 17a is exposed inside the chassis 18, and a circuit board (not shown) is electrically connected to the Pin photo 17a. The circuit board is fixed on the outside of the chassis 18 with its surface facing downward.

In the Pin photo 17a, a so-called synchronization signal is issued at the time when the laser light reflected by the timing adjusting mirror 16 is received, and after a predetermined time with reference to the time when this signal is generated, the semiconductor laser is recorded. The modulation drive is started by the information signal. In this way, scanning is started from the start position of the image recording medium with the beam modulated by the synchronization signal.

[0007]

Here, for the timing adjustment of the synchronizing signal, the timing adjusting mirror 16 is appropriately moved and fixed, that is, the support plate 16a for supporting the timing adjusting mirror 16 is mounted on the chassis 18. Since it is performed by appropriately moving and fixing it, the timing adjustment mirror support plate 16a for moving / fixing is inevitably required, and there is a problem that the cost of the apparatus increases.

The cylindrical lens 13a,
Polygon mirror 12, fθ lens 13b, fixed mirror 1
4, 15, the timing adjusting mirror 16, the Pin photo 17a, etc. are arranged at predetermined positions on the chassis 18,
Since the cover is sealed by a cover (not shown), the cover must be opened in order to adjust the timing of the synchronization signal, which causes a problem that the work becomes complicated.

Therefore, it is a first object of the present invention to provide an optical scanning device that does not require a reflection mirror support plate and can reduce the cost of the device.

Further, in addition to the first object, the present invention provides an optical scanning device which can perform timing adjustment of a synchronizing signal without opening a cover covering a chassis, thereby simplifying the work. The second purpose is to do so.

[0011]

In order to achieve the first object, the optical scanning device of the first means scans the light beam generating means for generating a light beam and the image recording area on the light receiving surface. In order to deflect and scan the light beam from the light beam generating means, the deflection scanning means and the light beam outside the image recording area among the light beams deflected by the deflection scanning means are received through a reflecting mirror. An optical scanning device comprising a photodetector capable of detecting a synchronization signal, wherein the reflection mirror is directly fixed to the chassis, and the substrate on which the photodetector is mounted is positionally adjusted with respect to the chassis. It should be installed as much as possible.

In order to achieve the above-mentioned second object, the optical scanning device of the second means, in addition to the above-mentioned first means, arranges a substrate on the lower side of the chassis and forms an opening in a part of the chassis. And projecting the photodetector into the chassis through this opening, forming a long hole in the substrate, and projecting a pin in the chassis that is loosely fitted in the long hole. By adjusting the relative position in the slot, the position of the photodetector with respect to the chassis can be adjusted.

In order to achieve the above-mentioned second object, the optical scanning device of the third means, in addition to the above-mentioned first means, arranges a substrate inside the chassis and perforates a long hole in the chassis. The position of the photodetector with respect to the chassis can be adjusted by projecting a pin that is loosely fitted in the elongated hole on the substrate and adjusting the position of the pin in the elongated hole.

[0014]

According to the optical scanning device in the first means, the reflection mirror is directly fixed to the chassis, and the substrate on which the photodetector is mounted is attached to the chassis in a positionally adjustable manner. The timing of the synchronization signal is adjusted, and the reflection mirror support plate is unnecessary.

According to the optical scanning device in the second means, the substrate is arranged on the lower side of the chassis, and the photodetector is projected to the inside of the chassis from the opening formed in a part of the chassis. A pin projecting from the chassis is loosely fitted in the slot formed in the slot, and the relative position of the pin in the slot is adjusted to adjust the position of the photodetector with respect to the chassis. Timing adjustments are made without opening the cover that covers the chassis.

According to the optical scanning device in the third means, the substrate is arranged inside the chassis, and the pins protruding from the substrate are loosely fitted and arranged in the elongated holes formed in the chassis. The position of the pin in the elongated hole is adjusted to adjust the position of the photodetector with respect to the chassis, and the timing of the synchronization signal is adjusted without opening the cover covering the chassis.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B show an optical scanning device according to an embodiment of the present invention. FIG. 1A is a plan view with a cover removed, FIG. 1B is a side sectional view of FIG. 1 is a cross-sectional view taken along the line AA in FIG. 1, and FIG. 3 is a bottom view of FIG. 2. The same components as those described in the prior art are designated by the same reference numerals to avoid duplication. The description here is omitted.

The optical scanning device of this embodiment is different from that of the prior art in that the reflection mirror (timing adjusting mirror described in the prior art) 16 is fixed directly to the chassis 18 without the support plate 16a, and The point is that the circuit board 1 on which, for example, the Pin photo 17a as a detector is placed and electrically connected, is attached to the chassis 18 in a positionally adjustable manner.

That is, as shown in FIG. 2, the circuit board 1 has a chassis 1 with its surface 1A facing downward.
8 is located below the pin photo 17a.
Is in a state of protruding inside the chassis 18 from an opening 18 b formed in the chassis 18. In addition, as shown in FIGS. 2 and 3, the circuit board 1 has elongated holes 1a.
On the other hand, the chassis 18 is provided with a pin 18a protrudingly fitted in the elongated hole 1a.

Therefore, the pin photo 1 is adjusted by adjusting the relative position of the pin 18a in the long hole 1a with the cover (not shown) attached to the chassis 18.
The position of the chassis 7a is adjusted with respect to the chassis 18, and the timing of the synchronizing signal is adjusted.

Then, the circuit board 1 is fixed to the chassis 18 by fastening means (not shown) in a state where the timing adjustment of the synchronizing signal is completed.

As described above, in this embodiment, the reflection mirror 16 is directly fixed to the chassis 18, and the Pin
The circuit board 1 on which the photo 17a is mounted is attached to the chassis 18 so that the position of the circuit board 1 can be adjusted, and the timing of the synchronizing signal is adjusted.
Since it is configured so as to be unnecessary, it is possible to reduce the cost of the device.

Further, the circuit board 1 is arranged below the chassis 18, and the pin photo 17a is projected from the opening 18b formed in a part of the chassis 18 to the inside of the chassis 18 to form a long hole in the circuit board 1. A pin 18a projecting from the chassis 18 is loosely fitted to the chassis 1a, and the relative position of the pin 18a in the elongated hole 1a is adjusted to adjust the position of the Pin photo 17a with respect to the chassis 18 to obtain a synchronization signal. Since the timing adjustment is performed without opening the cover that covers the chassis 18, the work can be simplified.

FIG. 4 is a sectional view of a photodetector and a circuit board portion of an optical scanning device according to another embodiment of the present invention. The optical scanning device of this embodiment is similar to the previous embodiment in that the reflection mirror 16 is directly fixed to the chassis 18, but the circuit board 1 is arranged so that the surface 1A faces upward. The pin photo 17 a is arranged inside the chassis 18 and is mounted on the circuit board 1. Further, the chassis 18 is provided with an elongated hole 18d having substantially the same shape as that described in the previous embodiment, while the circuit board 1 is provided with a pin 1b loosely fitted in the elongated hole 18d. It is set up.

Therefore, the position of the pin photo 17a with respect to the chassis 18 is adjusted by adjusting the position of the pin 1b in the elongated hole 18d with the cover not shown attached to the chassis 18, and the timing of the synchronization signal is adjusted. Adjustments are made.

That is, like the previous embodiment, it is possible to reduce the cost of the device and simplify the work.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say, for example, in the above embodiment, the Pin photo 17a is mounted on the electrically connected circuit board.
The circuit board may be the only board.

Further, in the above embodiment, the photodetector is a pin photo, but it is of course possible to replace it with another photoelectric conversion element.

In the above embodiment, an example in which the optical scanning device is applied to a laser beam printer is described, but the invention is not limited to the laser beam printer.
The same can be applied to other devices.

[0030]

As described above, according to the optical scanning device of the first invention, the reflecting mirror is directly fixed to the chassis, and the substrate on which the photodetector is mounted is attached to the chassis in a positionally adjustable manner. Adjust the timing of the sync signal,
Since the reflecting mirror support plate is not necessary, the cost of the device can be reduced.

According to the optical scanning device of the second invention, in addition to the first invention, the substrate is arranged below the chassis,
The photodetector is projected into the chassis from the opening formed in a part of the chassis, and the pin protruding from the chassis is loosely fitted in the long hole formed in the substrate. By adjusting the position, the position of the photodetector with respect to the chassis is adjusted, and the timing of the sync signal is adjusted without opening the cover that covers the chassis, which simplifies the work. It will be possible.

According to the optical scanning device of the third invention, in addition to the first invention, the substrate is arranged inside the chassis,
A pin protruding from the board is loosely fitted in an elongated hole formed in the chassis, and the position of the pin in the elongated hole is adjusted to adjust the position of the photodetector with respect to the chassis. Because it is configured to adjust the timing of without opening the cover that covers the chassis,
It is possible to simplify the work.

[Brief description of drawings]

1A and 1B show an optical scanning device according to an embodiment of the present invention, FIG. 1A is a plan view with a cover removed, and FIG. 1B is a side sectional view of FIG.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a bottom view of FIG.

FIG. 4 is a sectional view of a photodetector and a circuit board portion of an optical scanning device according to another embodiment of the present invention.

FIG. 5 is a plan view showing an optical scanning device in the related art, with a cover removed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 board 1a board long hole 1b board pin 11 light beam generating means 12 deflection scanning means 16 reflection mirror 17a photodetector 18 chassis 18a chassis pin 18b chassis opening 18d chassis long hole

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location H04N 1/113 (72) Inventor Mitsunaga Ozawa 14-888 Akaho, Komagane-shi, Nagano Stock company 3 Inside the Komagane factory, Kyoseiki

Claims (3)

[Claims] 1. A light beam generating means for generating a light beam, a deflection scanning means for deflecting and scanning the light beam from the light beam generating means for scanning an image recording area on a light receiving surface, and the deflection. An optical scanning device comprising: a photodetector capable of detecting a synchronizing signal by receiving a light beam outside the image recording area of the light beam deflected by the scanning means through a reflection mirror, wherein the reflection mirror is An optical scanning device in which the substrate on which the photodetector is mounted is attached to the chassis so as to be positionally adjustable while being fixed directly to the chassis. 2. The optical scanning device according to claim 1, wherein the substrate is arranged on the lower side of the chassis, and an opening is formed in a part of the chassis, and the photodetector is provided inside the chassis through the opening. The photodetector is formed by projecting a long hole in the substrate and a pin that is loosely fitted in the long hole in the chassis and adjusting the relative position of the pin in the long hole. Optical scanning device that enables position adjustment with respect to the chassis. 3. The optical scanning device according to claim 1, wherein the substrate is disposed inside the chassis, the chassis is provided with a long hole, and the substrate is provided with a pin loosely fitted in the long hole. An optical scanning device capable of adjusting the position of the photodetector with respect to the chassis by adjusting the position of the pin in the elongated hole.