KR970002940Y1 - Optical pick-up for optical disk player - Google Patents

Abstract

None.

Description

Optical pickup device of optical disc player

1 is a schematic perspective view of an optical system of a general optical pickup device.

2 is a perspective view of an optical system of the optical pickup device according to the present invention.

Figure 3 is an enlarged perspective view of the main part of the present invention.

4 is a light path diagram of an optical pickup apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

32: laser diode 34: reflecting surface

36: disk 38: detector

40: transmission surface 42: half reflection mirror

The present invention relates to an optical pickup device of an optical disc player, and more particularly, a beam splitter on a laser beam path in an optical system of an optical pickup device applied to an optical disc player such as a compact disc player (CDP) or a laser disc player (LDP). The collimator lens of the splitter is excluded, and the laser beam emitted from the laser diode is incident directly to the disk surface through the objective lens at the position, and the laser is reflected from the disk surface and passed through the objective lens. The present invention relates to an optical pickup device of an optical disc player that can simplify the structure of an optical system and maximize the efficiency of a laser beam by installing a reflecting half mirror that allows a beam to pass through a detector.

In general, the optical system of the optical pickup device 10, which is a major component of the optical disc player, has a laser diode 12, a diffraction grating 14, a beam splitter 16, as shown in FIG. The collimator lens 18 and the reflector 20 are installed on the same center line, and the objective lens 22 is installed at a position close to the disk in the vertical upper portion of the reflector 20, and the beam splitter 16 One side has a structure in which the detector 24 is installed.

In the optical system of the conventional optical pickup device, the laser beam emitted from the laser diode 12 passes through the diffraction grating 14 installed in front of the beam splitter 16 and passes through the beam splitter 16. One laser beam passes through the collimator lens 18 on the laser beam path and then enters the objective lens 22 by the reflector 20 to reach the disk surface.

Then, it is reflected back on the recording surface of the disk, reflected in the opposite path as it was when it was incident, divided into the detectors 24 in the beam splitter 16, and the information recorded on the disk surface was found.

However, in the optical system of the conventional optical pickup device, since the laser beam is often lost in the process of being sent back to the beam splitter and re-reflected, there is a problem that the utilization efficiency of the laser beam is very low, and various types of lenses are applied. As a result, the structure was also complicated.

The object of the present invention is to solve the above-mentioned problems. The optical beam of the conventional optical pickup device excludes the beam splitter, the collimator lens and the reflector, and at the same time the laser beam emitted from the laser diode vertically below the objective lens. The optical system of the optical pick-up device is simplified by installing a half reflector which is directly incident on the disk surface through the lens and is transmitted through the objective lens by reflecting from the disk surface. It is an object of the present invention to provide an optical pickup device of a new type of optical disc player which can maximize the performance.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The present invention, as shown in FIG. 2, excludes the beam splitter 16, the collimator lens 18 and the reflector 20 in the optical system of the optical pickup device 10, the laser diode vertically downward of the objective lens 30 (32) Reflective surface 34 for reflecting the laser beam emitted from the laser diode 32 in the front position toward the objective lens 30, and the laser reflected from the disk 38 surface through the objective lens 30 A detector for providing a half reflector 42 having a transmissive surface 40 through which the beam passes through the detector 38, and detecting a laser beam reflected from the disk surface 36 below the half reflector 42. 38) has been made by installing.

In the present invention, as shown in FIG. 3, the half reflector 42 is inclined at an angle of 45 ° to reflect the laser beam emitted from the laser diode 32 toward the objective lens 30. And a transmissive surface 40 for transmitting the laser beam reflected from the disk 36 surface toward the detector 38 is formed horizontally, and the reflecting surface 34 and the transmissive surface 40 are sequentially formed in a stepped manner. Formed.

At this time, the reflective surface 34 is coated with a material that does not transmit the laser beam (Coating) so that all the laser beam emitted from the laser diode 32 can be reflected to the objective lens (30).

The operation of the present invention as follows.

As shown in FIG. 4, the laser beam emitted from the laser diode 32 is reflected from the reflecting surface 34 of the half reflecting mirror 42 toward the objective lens 34 and is incident on the disk 36 surface. The laser beam reflected from the surface of the disk 36 and passed through the objective lens 30 passes through the transmission surface 40 of the half reflector 42 and is sent directly to the detector 38.

By applying the present invention, the laser beam emitted from the laser diode can be used to the maximum, so that the efficiency of the optical pickup device can be maximized. As the structure of the optical system is simplified, the workability and productivity are improved. The effect is that you can.

Claims (2)

In the optical system of the optical pickup device, the beam splitter 16, the collimator rent 18, and the reflector 20 are excluded, and the laser diode 32 is positioned in front of the laser diode 32 vertically below the objective lens 30. Reflecting surface 34 and disk 36 reflecting the emitted laser beam from the laser diode 32 to the objective lens 30 at the front position of the laser diode 32 vertically below the objective lens 30. A half reflector 42 having a transmissive surface 40 for transmitting the laser beam reflected through the objective lens 30 and passing through the detector 38 to the detector 38, and below the half reflector 42 vertically. And a detector (38) for detecting a laser beam reflected from the surface of said disk (36). According to claim 1, The half reflecting mirror 42 is installed to the reflective surface 34 inclined at an angle of 45 °, the transmissive surface 40 is installed horizontally, the reflective surface 34 and the transmissive surface 40 The optical pickup device of the optical disc player, characterized in that formed in succession step by step).