JPS60128411A - Optical system of recording device - Google Patents

Abstract

PURPOSE:To prevent the invasion of dust by covering a focusing lens, a polarizing means, a reflecting mirror, etc., with optical cases and arranging a laser light irradiating unit and a laser light position detecting unit on the border between the optical case and the external. CONSTITUTION:The laser light irradiating unit consisting of a laser holder 1 incorporating a laser and the focusing lens 2 is fitted to a part of a lower optical case 12 to separate the outside from the inside. Laser light projected from the lens 2 is reflected by a rotary polyhedral mirror 4, scans a slightly downward reflecting mirror 11 and is projected from a transparent projection window 13 to record information on a recording medium which is not shown in the drawing. The light reflected by the rotary polyhedral mirror 4 is reflected by a sensor mirror 9 fixed on a holder 8 and detected by an optical sensor 5 fitted to the lower optical case 12 and a signal is transmitted to a control part not shown in the drawing. Optical systems other than the laser light irradiating unit and the optical sensor 5 are coverted with the lower and upper optical cases 12, 14 and a packing is inserted between both the cases. Consequently, the invasion of dust is prevented and a light source unit or the optical sensor is easily replaced.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an optical system of a recording apparatus that records image information such as a character or figure on a recording medium at high speed using a laser beam.

<Technical background of the invention and its problems> In general, a recording device that records image information such as letters and figures on a recording medium at high speed using a laser beam focuses and deflects the laser beam using an optical device to record the image information on the recording medium. let it scan,
Image information is recorded on a recording medium by modulating a laser beam with a recording signal. The optical device includes a laser beam irradiation unit that emits a laser beam and focuses it on the recording medium, a deflection unit that deflects the laser beam to scan the recording medium, and a position detection unit that detects the scanning position of the deflected laser beam. A device consisting of a sensor unit and a mirror unit that guides the deflected laser beam onto the recording medium and onto the position detection sensor unit.Each unit that makes up these optical devices is configured with a mechanism and a developer floating inside or outside the recording device. In order to prevent deterioration in performance due to adhesion of wear particles, dust, etc. to the parts, the optical system of the recording device must be housed in an optical case provided with a light-transmitting portion that emits a laser beam.

In this case, the wiring for the laser beam irradiation unit and the position detection sensor unit will be routed through a wiring hole drilled in the optical case, and the above-mentioned developer, abrasion powder, and dust will be removed from the gap between the wiring hole and the signal line. It is conceivable that a tight rubber bushing could be fitted to prevent the intrusion of foreign substances.

When assembling such an optical system, there is a problem in that it takes time and effort to pass the laser beam irradiation unit and the position detection sensor unit through the wiring hole into which the rubber bushing is fitted, resulting in a long assembly time.

Also, since the sensor light receiving part of the position detection sensor unit is only about 1 to 2 mm wide, a measuring instrument is used to adjust the laser beam to scan the sensor light receiving part during assembly. Since the unit is fixed inside the optical case, adjustment is extremely difficult, and furthermore, if either the laser beam irradiation unit or the upper position detection sensor unit breaks down after the optical system is installed in the recording device, When it is necessary to replace the unit due to its lifespan, etc., the optical case must be disassembled and replaced and adjusted, and at this time a lot of developer, abrasion powder, dust, etc. are introduced into the optical case. There is a lot of danger.

FIG. 3 is a schematic configuration diagram of an optical system including the above-described optical case.

In Fig. 3, numeral 1 denotes a laser holder holding several semiconductor lasers (not shown), and a focusing lens 2 that focuses the laser beam and a lens holder 3 that holds the focusing lens 2 and enables focus adjustment. It forms a light irradiation unit. 4 is a rotating polygon mirror of a deflection unit that deflects the laser beam irradiated from the laser beam irradiation unit.

Reference numeral 5 denotes a sensor light receiving section, which is attached to a sensor substrate 6 and forms a position detection sensor unit together with a sensor holder 7. The position detection sensor unit is used to detect the scanning position of the laser beam deflected by the polarization unit.When using a deflection unit that performs deflection by rotating a large number of reflective surfaces, such as a rotating polygon mirror, It is used to correct division errors and uneven rotational speeds of each reflecting surface.

The light receiving area of the sensor light receiving section 5 of the position detection sensor unit is 1 to 21! Since the width is only about #, the laser beam is adjusted to ensure that it scans the sensor light receiving area during assembly and adjustment. Therefore, the sensor substrate /-6 to which the sensor light receiving section 5 is attached is held in the sensor holder 7 so as to be adjustable.

The laser beam deflected by the deflection unit is guided to a multi-position detection sensor unit by a sensor mirror 9 fixed to a sensor mirror holder 8, as shown by a dashed line. A reflective mirror holder 10 is attached to a recording medium (not shown).
The light is guided from a solid line to a broken line through an exit window 13 provided in a lower optical case 12 by a reflecting mirror 11 fixed slightly downward. Note that the exit window 13 is provided with a galanium plate coated with a non-reflective coating for dust prevention.

Now, when the rotating polygon mirror 4 rotates in the direction of arrow a, the laser beam emitted from the laser beam irradiation unit is polarized by the rotating polygon mirror 4, and first reflected by the sensor mirror 9, and then reflected by the position detection sensor unit. The sensor light-receiving section 5 is scanned. At this time, the output signal of the position detection sensor unit is outputted to the control section of the recording apparatus through the signal line 16.

As the rotating polygon mirror 4 further rotates, the laser beam is reflected obliquely downward by the reflecting mirror 11, and the lower optical case 1
The light passes through the exit window 13 of No. 2 and starts scanning on the recording medium.

After a certain timing after the output signal is issued from the position detection sensor unit, the control section of the recording apparatus determines that the laser beam has reached the recording start point, and the recording signal is emitted onto the signal line 17.

The optical system consisting of each of these units is housed in an optical case to prevent the developer, abrasion powder, dust, etc. inside the recording apparatus from adhering thereto.

The optical case consists of a lower optical case 12 that serves as the base of the optical system and an upper optical case 14 that serves as a lid.
A sealing material 15 is fitted between the lower optical case 12 and the upper optical case 14 to prevent a gap from forming.

There are wiring holes 18.19 in the side wall of the lower optical case 712, and signal lines 16.1 connecting the position detection sensor unit and the V-ray irradiation unit to the control unit of the recording device, respectively.
7 is passing through. Rubber bushings 2 are installed in wiring holes 18° and 19.
0.21 is fitted, so that there is no gap between the signal lines 16, 17 and the wiring holes 18, 19, and prevents developer, abrasion powder, dust, etc. from entering.

In this way, the optical system is completely covered and protected by the optical case (12, 14), but this makes the assembly process difficult. Especially the position detection sensor unit and V-
It is necessary for the laser beam irradiation unit to exchange signals with the control unit of the recording device via the signal line 16.17, and the wiring of the signal line 16.17 between the position detection sensor unit and the laser beam irradiation unit is at the bottom. This is done through the wiring holes 18 and 19 of the optical case 12. Naturally, signal line 16
There is a connector at the tip of 17 to connect to the control unit, which gets in the way when the rubber pushers 20 and 21 are passed through, making assembly difficult.

Furthermore, since the lower optical case 12 has a box shape, it is useful for adjusting the optical axis of the sensor light receiving section 5 of the position detection sensor unit after assembly, for connecting the measuring instrument to the sensor board, and for moving and fixing the sensor board. is very difficult to do.

Furthermore, if the position detection unit or laser beam irradiation unit malfunctions or has expired after the optical system has been installed in the recording device, and the unit needs to be replaced or readjusted, the optical case must be disassembled. In addition, there is a high risk that developer, abrasion powder, dust, etc. may enter the optical case.

<Objective of the Invention> The present invention has been made in view of the above points, and it is possible to facilitate the wiring process when assembling the optical system, and at the same time facilitate the optical axis adjustment of the sensor light receiving part of the position detection sensor unit. To achieve this objective, the optical system of the recording device of the present invention is an optical system that includes a semiconductor laser light source, a focusing lens, a deflection mechanism, and a reflecting mirror. an optical case having a transparent portion that emits the semiconductor laser beam and covering the optical device to prevent dust from adhering to the optical device;
A laser beam irradiation unit including the above semiconductor laser light source and a focusing lens, a position detection sensor unit that detects the scanning position of the deflected laser beam, and the above laser beam irradiation unit and position detection sensor unit A means for attaching the optical case to the optical case from outside the optical case so as to be located at the boundary between the optical case and the outside, and the laser beam irradiation unit and the position detection sensor unit are attached to a part of the optical case. This optical case is configured to have a sealed structure.

<Embodiment of the Invention> An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a schematic configuration diagram showing an embodiment of the optical system of the recording apparatus of the present invention, and the same parts as the apparatus shown in FIG. 3 are designated by the same reference numerals. .

In FIG. 1, reference numeral 1 denotes a laser holder to which a semiconductor laser (not shown) is attached, and a focusing lens 2 that focuses the laser beam and a lens holder 3 that holds this focusing lens 2 and enables focus adjustment, the laser beam is It forms an irradiation unit and is attached to the outer wall surface of the lower optical case 712 from the outside with screws 23 as will be described later.

4 is a rotating polygon mirror of a deflection unit that deflects the laser beam irradiated from the laser beam irradiation unit. Reference numeral 5 denotes a sensor light receiving section, which is attached to the sensor substrate 6 to form a position detection sensor unit, and is attached from the outside to the outer wall surface of the lower optical case 712 with screws 31 so as to have a sealed structure, for example, via a sealing material. There is. A laser beam deflected by the rotating polygon mirror 4 of the deflection unit is guided to the sensor light receiving section 5 of the position detection sensor unit by a sensor mirror 9 fixed by a sensor mirror holder 8 as shown by a chain line. A rotating polygon mirror 4 is connected to a recording medium (not shown).
The laser beam deflected by is guided by a reflection mirror 11 fixed slightly downward to a non-conforming mirror holder 10 through an exit window 13 provided in a lower optical case 12 as shown by a solid line → broken line. Incidentally, the exit window 13 is provided with a glass plate provided with a non-reflective coating 1 for dustproofing. The method for recording image information on the recording medium of the optical system is the same as the example shown in FIG. 3, so a description thereof will be omitted.

The lower optical case 712 serves as the base of the optical system and has a box shape, while the upper optical case 14 serves as the lid.
The optical case is made up of:

A seal lug 15 is fitted between the lower optical case 12 and the upper optical case 14 so that there is no gap.

The position detection sensor unit and the laser beam irradiation unit are attached to the lower optical case 12 from the outside, and there is no need to pass the signal lines 16 and 17 through wiring holes as in the conventional case, making assembly very easy.

Further, the optical axis adjustment of the sensor light receiving section of the position detection sensor unit after assembly can be performed very easily.

A method for adjusting the optical axis of the sensor light receiving section of the position detection sensor unit will be explained with reference to FIG.

As shown in FIG. 2, the position detection sensor unit is attached to the outer wall of the lower optical case 12 from the outside. The sensor board 6 is mounted by pressing the sensor board 6 against the outer wall with several screws 23, for example, through a sealing material so as to form a sealed structure. A sensor board 6 is installed in the lower optical case 12.
There is a hole 22 smaller than the size of the hole 22, which allows the laser beam to enter the sensor light receiving section 5 as shown by the solid line. A check terminal 24 is provided on the outside of the sensor board 6, and a measuring device such as a voltmeter 25 or a synchroscope can be easily connected to the check terminal 24.

Now, if the laser beam is shifted as shown by the broken line, the laser beam cannot enter the sensor light receiving section 5.

In order to cause the laser beam shown by the broken line to enter the sensor light receiving section 5, the sensor substrate 6 may be shifted in the direction shown by the arrow d. It can be easily shifted by hand by slightly loosening the screw 23, but by using a jig 26 shown in FIG. 2, it can be easily done while observing a measuring device such as a voltmeter 25.

When the jig 26 is inserted into the hole 27 provided in the outer wall of the lower optical case 712 and the jig 26 is rotated as shown by the arrow C, the end of the sensor board 6 is pushed by the jig 26 due to the eccentric shaft, and the jig 26 is rotated as shown by the arrow d. The sensor board 6 moves in the direction. Perform this work while watching the measuring device such as the voltmeter 25, and stop moving the sensor board when the laser beam enters the sensor light receiving section 5 and the maximum output is obtained from the measuring device, and tighten the screw 23 to fix the sensor board 6. .

As described above, in the present invention, the optical system can be easily assembled, and the optical axis of the sensor light receiving section of the position detection sensor unit can also be easily adjusted.

<Effects of the Invention> As explained above, according to the present invention, a laser beam irradiation unit and a position detection sensor unit having a signal line,
By adopting a structure that attaches to the outer wall of the optical case from the outside of the optical case, there is no need to provide a wiring hole in the optical case, making wiring easier and improving the assembly of the optical system, as well as the laser beam irradiation unit and position detection sensor. When the unit is attached, these form a part of the optical case.1 The optical case has a sealed structure, which prevents developer, abrasion powder, dust, etc. from entering the optical case. Furthermore, even if it becomes necessary to replace the position detection sensor unit or laser beam irradiation unit due to malfunction, end of life, etc., the desired unit can be replaced without separating the lower optical case and the upper optical case, preventing the intrusion of dust etc. It is possible to prevent this as much as possible, and it is also possible to easily correct optical axis deviation of the sensor light receiving part of the position detection sensor due to unit replacement.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the optical system of the recording apparatus of the present invention, FIG. 2 is a diagram showing the detailed configuration of the position detection sensor unit, and FIG. 3 is a diagram for explaining the basic technology of the present invention. FIG. 2 is a schematic configuration diagram showing an example of an optical system of a recording device provided. 1...Laser holder, 2.Focusing lens, 4...
Rotating polygon mirror, 5...Sensor light receiving section, 6...Sensor board, 11...Reflection mirror, 12...Lower optical case, 13...Emission window, 14...Upper optical case,
23... Position detection sensor unit mounting screw, 31 Laser beam irradiation unit mounting screw. Agent Patent attorney Aihiko Fuku (and 2 others) Figure 2

Claims (1)

[Scope of Claims] 1. An optical device including a semiconductor laser light source, a focusing lens, a deflection mechanism, and a reflecting mirror, and a light-transmitting portion that emits the semiconductor laser beam, and prevents dust from adhering to the optical device. an optical case that covers the optical device in order to prevent this, a laser beam irradiation unit that includes the semiconductor laser light source and a focusing lens, and a position MFA that detects the scanning position of the deflected laser beam.
mounting means that can be accessed from the outside of the optical case to the optical case so that the output sensor unit, the laser beam irradiation unit 1- and the position detection sensor unit are located at the boundary between the optical case and the outside; An optical system for a recording apparatus, characterized in that the laser beam irradiation unit and the position detection sensor unit are configured to form a part of the optical case, and the optical case has a sealed structure.