KR100349511B1 - Separable optical system and framing method thereof - Google Patents

Abstract

The present invention discloses a split optical system.

According to the present invention, a first light source for scanning a laser beam having a predetermined wavelength is positioned on one side, and a six-sided beam splitter, a mirror and a collimator lens, an objective lens, and an actuator are sequentially positioned on a path of the beam scanned from the first light source. Main base; A sub-base fixedly installed at a side of the main base, and having a second light source for scanning a laser beam having a wavelength different from that of the first light source at one side thereof, and a flat base beam splitter, a focusing lens, and a photodiode sequentially positioned on the front surface thereof; In this case, the first and second light sources may be installed on different bases, and the three-dimensional adjustment unit generated by installing the first and second light sources on the existing main base may be omitted through an assembly process of fixing them. .

Therefore, there is an advantage that can significantly improve the assembly.

Description

Separable optical system and framing method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical system, and more particularly, to a split type optical system having a plurality of light sources for reproducing compact discs and digital video discs.

In general, optical discs have been relatively widely used in recent years because they can be recorded / reproduced with a relatively high density compared to LPs or magnetic recording tapes, and are particularly semi-permanent.

The most widely used and widely used as such an optical disk is a compact disk (hereinafter abbreviated as CD).

However, such a compact disc has a limited recording capacity. For example, such a compact disc cannot be easily used for movies, music, games, and other multimedia for more than 90 minutes, and at least two compact discs have to be repeatedly played and satisfied.

In order to solve this problem of compact discs, digital video discs (DVDs), which are the next generation optical discs, have been developed in recent years. Such DVDs have a storage capacity of about 25 times that of CDs, Can read 10 million bits of data. This is because such DVDs have about half as many feet and tracks as CDs. In other words, since one pit of data and a track are about 0.4 feet and about 0.8 microns in DVD, high density recording is possible.

Thus, due to its large capacity and high operability, it is expected that DVD will be easily used in various sectors such as music, movies, games and other multimedia.

On the other hand, when playing such a DVD, it is desirable to satisfy the needs of consumers, as compared to providing a player that can use only DVD, so that the most widely used CD can be satisfied. The development of an optical pickup capable of reproducing all of these has been steadily pursued.

1 shows an optical system using two light sources for playing CD and DVD together.

It has a main base 10.

On one side of the main base 10, laser diodes for scanning a beam of 780 nm wavelength and a beam of 650 nm wavelength are respectively provided as the first light source 20 and the second light source 30 so as to be spaced apart by a predetermined interval.

A cubic beam splitter 40 and a flat beam splitter 50 are positioned in front of the first and second light sources 20 and 30, and the disk D, that is, the compact disk or As for reflecting the beam toward the digital video disk, there are located a reflecting mirror 60, a collimating lens 70 for shaping the beam, an objective lens 80 for focusing the beam on the disk D, and the like. .

In addition, a light receiving element, that is, a photodiode 90 is arranged on the main base 10 to detect a signal from a beam reflected from the disk D.

However, in the optical system using such a conventional two-light source, there is a problem in that the assembly of each part is very difficult and causes a decrease in the assembly workability.

This problem is caused by providing a plurality of light sources, that is, the first and second light sources 20 and 30 on one main base 10.

That is, in the process of installing each component or the like on the main base 10, first, the optical system for DVD, whose strictness is limited, is assembled on the main base 10. In other words, after assembling optical components and actuators on the main base, the first light source 20 for the digital video disc is installed on the main base 10.

The photodiode 90 is adjusted two-dimensionally in the X and Y directions and then fixed.

The optical system for the CD is assembled with the optical system for the DVD assembled as described above. Thus, in adjusting the second light source 30 for the CD, three-dimensional adjustment, that is, adjustment in the X, Y, and Z directions should be made. do.

However, since it is very difficult to adjust the second light source 30 three-dimensionally in this way, the assembly is degraded.

The present invention was created to solve the problems of the conventional two-light source optical system, and the object of the present invention is to provide a detachable optical system that can be improved assembling performance by assembling the optical system by only two-dimensional adjustment without three-dimensional adjustment. have.

1 is a plan view of a general optical system,

2 is a plan view conceptually showing a separate optical system according to the present invention.

<Description of the symbols for the main parts of the drawings>

100: main base 110210: first and second light sources

120: six-sided beam splitter 130: mirror

140: collimator lens 150: objective lens

160: actuator 200: sub-base

220: flat beam splitter 230: focusing lens

240: photodiode

In order to achieve the above object, the split optical system according to the present invention has a predetermined optical system for reproducing a compact disc and a digital video disc through first and second light sources for scanning laser beams having different wavelengths. A first light source for scanning a laser beam having a wavelength, the main base having a six-sided beam splitter, a mirror and collimator lens, an objective lens and an actuator sequentially positioned on a path of the beam scanned from the first light source; The sub-base is fixedly installed on the side of the main base, the second light source for scanning a laser beam of a wavelength different from the first light source is located on one side, the flat base beam splitter, a focusing lens and a photodiode sequentially It is characterized by consisting of;

One preferred feature of the invention is that a first light source located in the main base is a laser diode for a digital video disc scanning a wavelength of 650 nm, and a second light source mounted on the sub base is a compact disc scanning a wavelength of 780 nm. It is a thing for the laser diode.

Hereinafter, a preferred embodiment of the split optical system according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram conceptually showing a separate optical system according to the present invention.

As shown therein, the split optical system according to the present invention includes a main base 100 on which the first light source 110 is installed and a sub base 200 on which the second light source 210 is installed. do.

The main base 100 provided with the first light source 110 reflects a beam between a cubic beam splitter 120 installed on a path of a beam scanned from the first light source 110 and a disk. A mirror 130 for shaping, a collimator lens 140 for shaping the beam, an objective lens 150 and an actuator 160 for focusing the beam on the disk are sequentially arranged.

The sub-base 200 in which the second light source 210 is installed is fixed to one side of the main base 100 by fixing means, for example, an adhesive, and the like, and the beam scanned from the second light source 210 and the main base A flat beam splitter 220 positioned on the path of the beam reflected by the mirror, a focusing lens 230 for focusing the beam, and a signal for detecting a signal from the beam reflected from the mirror of the main base. Photodiodes 240 as light receiving elements are arranged in sequence.

Meanwhile, the first light source 110 provided on the main base 100 described above is a laser diode for a digital video disk that scans a 650 nm wavelength beam, and the second light source 210 provided on the sub base 200. ) Is a laser diode for a compact disc that scans a 780 nm wavelength laser beam.

The assembly process of the split optical system according to the present invention having such a configuration will be described as follows.

First, if the optical system for the CD is configured separately, the sub-base 200 is fixed to a position designed on one side of the main base 100.

The compact disc laser diode, that is, the second light source 210 is adjusted in the Z-axis direction, and the photodiode 240 serving as the light receiving element is adjusted in the X and Y directions to complete the optical system for the CD.

As such, the sub-base 200 in which the second light source 210 and the photodiode 240 are installed forms one fixture.

Next, the optical component for DVD is adjusted on the optical system for CD.

That is, the DVD first light source 110 is adjusted in the Z-axis direction and fixed.

Then, the final stage and the sub base 200 are adjusted in the X and Y-axis directions with respect to the main base 100, and then fixed by an adhesive to complete one separate optical system.

As described above, according to the split optical system according to the present invention, the first and second light sources are installed on different bases, and the first and second light sources are installed on an existing main base through an assembly process of fixing them. The three-dimensional adjustment section can be omitted.

Therefore, there is an advantage that can significantly improve the assembly.

Claims (4)

In constructing an optical system for reproducing compact discs and digital video discs through first and second light sources for scanning laser beams of different wavelengths, A first light source for scanning a laser beam of a predetermined wavelength is located on one side, and a six-beam splitter on the path of the beam scanned from the first light source, a mirror for reflecting the beam between the disk, and shaping the beam A main base on which a collimator lens and an objective lens and an actuator for focusing the beam on the disk are sequentially located; And It is fixed to the side of the main base, a second light source for scanning a laser beam of a wavelength different from the first light source is located on one side, the beam scanned from the second light source and the beam reflected by the mirror of the main base A sub-base in which a plate-shaped beam splitter positioned on a path of the light source, a focusing lens for focusing the beam, and a photodiode as a light receiving element for detecting a signal from the beam reflected from the mirror of the main base are sequentially located; Separate optical system, characterized in that consisting of. The method of claim 1, The first light source positioned on the main base is a laser diode for a digital video disc scanning a wavelength of 650 nm, and the second light source installed on the sub base is a laser diode for a compact disc scanning a wavelength of 780 nm. Detachable optical system. Fixing the sub base to a position designed on one side of the main base; Adjusting the second light source in the Z-axis direction; Adjusting the light receiving element in the X and Y axis directions perpendicular to the Z axis; Adjusting and fixing the first light source in the Z-axis direction; And And adjusting the sub base in the X and Y axis directions with respect to the main base and then fixing the sub base. The method of claim 3, wherein And said first light source is a laser diode for a digital video disc, and said second light source is a laser diode for a compact disc.