JPS62167630A - Optical recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain light weight and miniaturization of an optical conversion section by constituting the optical conversion section by a light collection mirror in an optical recording and reproducing device recording and reproducing the information optically to a recording face. CONSTITUTION:After a laser beam 3 emitted from a semiconductor laser 2 is converted into a collimated light by a collimator lens 4, the beam is bent at a right angle by a beam splitter 5. Then the progressing direction of the laser beam 3 is bent upward by the light collection mirror 21 and focused to a focal point P, then then laser beam 3 is irradiated to a recording face 1a of a recording medium 1 as a spot. Then the laser beam 3 modulated by the information recorded on the recording face 1a goes backward to the light path, converted into the collimated by the light collection mirror 21, the progressing direction is bent at a right angle, the laser beam 3 goes straight to a spectral face 6 of the beam splitter 5 and reaches a sensor part 12. Thus, the light conversion section is made light in the weight and miniaturized.

Description

[Detailed description of the invention] [Industrial application field] The present invention optically records information on a recording medium.

The present invention relates to an optical recording/playback device for playback.

[Conventional technology]

Conventionally, information previously recorded on a recording medium is optically reproduced, new information is optically recorded on the recording medium, or at least one of these two functions. Optical recording/reproducing devices with such functions are known.

A conventional optical recording/reproducing device is shown in FIG.

First, in the figure, 1 indicates a recording medium.

Further, 2 is a semiconductor laser, and the semiconductor laser 2 is provided so as to emit a laser beam 3 upward.

A collimator lens 4 is provided directly above the semiconductor laser 2 . The collimator lens 4 converts the laser beam 3 emitted from the semiconductor laser 2 into parallel light.

A beam splitter 5 is arranged directly above the collimator lens 4. The beam brick 5 has a spectral surface 6
have. The spectral plane 6 reflects or transmits the incident light, and the laser beam 3 is bent at a right angle in its traveling direction by reflection, so that it travels to the left in the figure.

Further, 7 indicates a reflecting mirror. The reflecting mirror 7 is provided directly below the recording medium 1 and right next to the beam splitter 5. Here, the reflective surface 8 of the reflective mirror 7 is inclined at 45 degrees with respect to the horizontal plane. Therefore, the laser beam 3 bent at right angles by the beam splitter 5 is bent upward by the reflecting mirror 7.

An objective lens 9 is provided directly above the reflecting mirror 7. The objective lens 9 is composed of a convex lens.

The objective lens 9 and the reflection mirror 7 allow the light conversion unit 1
0 is configured. The light conversion unit 10 is driven by the drive unit 10, and can move in the direction of arrow A-B in the figure, and
The objective lens 9 is driven by a drive section, and is indicated by an arrow C-- in the figure.
It is possible to move in direction B. Therefore, the light conversion section 1
0 aligns the focal point of the objective lens 9 with the recording surface 1a of the recording medium 1 by moving in the direction of arrow A-B, and the objective lens 9 moves in the direction of arrow C-B. As a result, the focus of the objective lens 9 can be aligned to a desired track on the recording surface 1a.

Next, the operation will be explained.

A laser beam 3 emitted from a semiconductor laser 2 is converted into parallel light by a collimator lens 4, and then bent at a right angle by a beam splitter 5. Thereafter, the traveling direction of the laser beam 3 is bent upward by a reflection mirror 7, focused by an objective lens 9, and irradiated onto the recording surface 1a of the recording medium 1 in the form of a spot.

The laser beam 11 modulated according to the information recorded on the recording medium 1 travels backward along the optical path, is converted into parallel light by the objective lens 9, and is then bent at a right angle by the reflecting mirror 7. After that, the laser beam 11
The beam propagates straight through the spectral plane 6 of the beam splitter 5 and reaches the sensor section 12, where information is detected.

[Problem that the invention seeks to solve]

However, the optical head section of the optical recording/reproducing apparatus according to the prior art has the following problems.

That is, since the light conversion section 10 is composed of two members, the reflection mirror 7 and the objective lens 9, not only does the weight increase when moving, but also when the objective lens 9 focuses on the recording surface la, the reflection mirror 7, the movable distance must be ensured, and therefore, there is a problem in that it is difficult to make it compact.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and its purpose is to reduce the weight and size of the light conversion unit by optical recording/recording.
The present invention provides an optical head section of a playback device.

[Means for solving problems]

In the present invention, the light conversion section is configured by a condensing mirror.

[Effect]

The condensing mirror bends the incident light at right angles and emits it, and condenses the emitted light into a spot on the recording surface.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 5. Note that the same components as those in the prior art are given the same reference numerals, and the description thereof will be omitted.

Therefore, in the present invention, the objective lens 9 and the reflecting mirror 7 in the prior art are not provided, but a condensing mirror 21 is provided instead. The condensing mirror 21 is driven by a drive unit (not shown) and can move in the direction of the arrow AB and the direction of the arrow CB. Here, a reflecting surface 22 is formed on the condensing mirror 21 as shown in FIGS. 2 and 3. As shown in FIGS. The reflective surface 22 is formed by a paraboloid of revolution having an axis l inclined at 45 degrees with respect to the horizontal plane 23, and is positioned by the driving unit so that its focal point P coincides with the recording surface 1a of the recording medium 1. ing.

Next, the effect will be explained.

A laser beam 3 emitted from a semiconductor laser 2 is converted into parallel light by a collimator lens 4, and then bent at a right angle by a beam splitter 5. Thereafter, the traveling direction of the laser beam 3 is bent upward by the condensing mirror 21 and condensed at the focal point P, so that the laser beam 3 is irradiated onto the recording surface 1a of the recording medium 1 in the form of a spot. Become.

The laser beam 3 modulated by the information recorded on the recording surface 1a travels backward along the optical path, is converted into parallel light by the condensing mirror 21, and is bent at a right angle in its traveling direction. Thereafter, the laser beam 3 travels straight through the spectral plane 6 of the beam splitter 5 and reaches the sensor section 12 .

FIG. 4 shows recording of information on a plurality of recording media 1.

FIG. 3 is a diagram showing a state in which reproduction is performed.

Note that the condensing mirror 21. Beam splinter 5° sensor section 12. The semiconductor laser 2 and the like may be provided on the same substrate A as shown in FIG.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to reduce the weight and size of the light conversion section that bends incident light at right angles and focuses the light into a spot on the recording surface.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an optical recording/reproducing device according to the present invention,
Fig. 2 is a perspective view of the condensing mirror, Fig. 3 is a side view of the condensing mirror, Fig. 4 is a simplified configuration diagram of an optical recording/reproducing device equipped with a plurality of recording media, and Fig. 5 is a modified example. FIG. 6 is a block diagram showing the prior art. DESCRIPTION OF SYMBOLS 1... Recording medium, la... Recording surface, 21... Condensing mirror. Agent Masuo Oiwa (and 2 others) 1st
Zutomi 2 Figure 3rlA Figure 4 Figure 5 Figure 6 Procedural amendment (self-government, Showa year, month, day, Ministry of Licensing Office Chief's Palace 2, name of invention Optical recording/reproducing device 3, person making the amendment Relationship with the case) Patent Applicant Address 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Name (601) Mitsubishi Electric Corporation Representative Moriya Shiki 4, Agent Address 2-2-3-1 Marunouchi, Chiyoda-ku, Tokyo
, N (○゛,・ 5, 7+li Detailed description and drawings column of the positive subject invention. 6. Contents of amendment fil In the first line of page 5 of the specification, the phrase "to be present" has been changed to "
``Because of the large number of parts, the number of parts is large.'' (2) On page 5, line 8 of the same book, the phrase “light conversion section” was replaced with “
In addition to reducing the number of parts in the light conversion section," (3) The same book, page 6, lines 9 to 11, “The reflective surface 2
2 is formed by...
The reflective surface 22 is formed by a curved surface forming a concave shape,
and correct it. (4) In the 16th line of page 7 of the same book, the phrase ``optical conversion section'' has been corrected to read, ``The number of parts in one optical conversion section can be reduced.'' (5) The drawings, Figures 3 and 4 shall be amended as shown in the attached sheet. Above Figure 3 Figure 4

Claims (1)

[Claims] a recording medium having a recording surface on which information is recorded; and a light conversion unit that bends incident light at right angles, emits it at right angles to the recording surface, and focuses the emitted light into a spot on the recording surface. An optical recording/reproducing device which optically records and reproduces information on the recording surface, characterized in that the light conversion section is constituted by a condensing mirror. .