JPH087533Y2 - Optical pickup semiconductor laser light quantity adjusting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a semiconductor laser light amount adjusting device for an optical pickup used in a compact disc player, a video disc player, and the like.

[Outline of the device] A control circuit for controlling the emitted light quantity of the semiconductor laser of the optical pickup is provided in the player body, and a semi-fixed resistor for adjusting the light quantity is provided near the connector of the flexible board connecting the optical pickup and the player body. And a semi-fixed resistor for adjusting the light amount, which is connected to a control circuit via a connector, is a semiconductor laser light amount adjusting device for an optical pickup.

[Prior Art] Conventionally, as a light quantity adjusting means for adjusting the emitted light quantity of a semiconductor laser incorporated in an optical pickup,
A semiconductor laser auto power control circuit (hereinafter referred to as the APC circuit) built into the optical pickup, an APC circuit provided on the player side, and a semi-fixed resistor for adjusting the light amount in series with the semiconductor laser monitor diode. It is known that the other APC circuit is provided on the player body side.

However, is an obstacle to downsizing the optical pickup, and since the light quantity cannot be adjusted by the optical pickup alone, the light quantity must be adjusted after the optical pickup is assembled in the player body. , Had a drawback in that the semi-fixed resistor for adjusting the light amount was connected in series with the monitor diode, which had a restriction on the circuit configuration of the APC circuit.

[Problems to be Solved by the Invention] The purpose of the present invention is to improve the drawbacks of the above-described conventional device, and it does not become an obstacle when downsizing the optical pickup, and the light amount can be adjusted by the optical pickup alone. It is an object of the present invention to provide a semiconductor laser light amount adjusting device for an optical pickup that is capable of achieving the above and is not restricted by the circuit configuration of the APC circuit.

[Means for Solving Problems] In order to achieve the above-mentioned object, a semiconductor laser light quantity adjusting device for an optical pickup according to the present invention is (a) provided with a player main body to adjust the emitted light quantity of a semiconductor laser. A control circuit for controlling, (b) a flexible board having a connector connected to the optical pickup and connected to the player main body at the tip, and (c) the flexible board provided on the flexible board near the connector and the control via the connector. It is composed of a semi-fixed resistor for adjusting the amount of light connected to the circuit.

[Operation] By doing so, the light amount can be adjusted by itself when the optical pickup is manufactured, and a predetermined light amount can be obtained without adjusting again when the optical pickup is assembled into the main body.

[Embodiment] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an optical pickup and a player main body board, FIG. 2 is a circuit diagram of an electric system of the optical pickup, and FIG. 3 is a circuit diagram of an APC circuit.

A flexible substrate 2 is connected to the optical pickup 1, a semi-fixed resistor 3 for adjusting the light amount is provided near a connector 4 formed at the tip of the flexible substrate 2, and both terminals thereof are directly connected to the connector 4.

In addition, the optical pickup 1 is provided with an electric system such as a semiconductor laser 7 including a laser diode 7a and a monitor diode 7b, a photodetector 8 for detecting focus and tracking, a drive coil 9 for an actuator, and the like. Board 5
All electrical systems are connected to the corresponding circuits formed on the player main body board 5 by connecting to the connectors 6 provided on the.

The semiconductor laser 7 and the semi-fixed resistor 3 are, as shown in FIG. 3, an APC provided on the player main body substrate 5.
Independently connected to the circuit.

To adjust the amount of light emitted from the objective lens of the optical pickup 1, use the AP for adjustment of the optical pickup 1.
It is only necessary to connect to the C circuit and adjust the semi-fixed resistor 3 to obtain a predetermined amount of light, and it is not necessary to make adjustments after it has been installed in the player body.

Although the semi-fixed resistor 3 is provided near the connector 4 of the flexible substrate 2 in the above embodiment, it may be provided in the main body of the optical pickup 1.

Further, the semi-fixed resistor 3 is not limited to the two-terminal type, but a three-terminal type can also be used, which is AP
The degree of freedom in the circuit configuration of the C circuit is great.

The wiring means for connecting the optical pickup 1 and the player main body substrate 5 is not limited to the flexible substrate 2,
Other known ones, for example, a bundle of ordinary connecting cords may be used.

[Effects of the Invention] As described above, the semiconductor laser light quantity adjusting device for an optical pickup of the present invention includes a control circuit provided in the player body for controlling the emitted light quantity of the semiconductor laser.
The semi-fixed resistor for adjusting the light quantity is provided in the optical pickup, and the semi-fixed resistor for adjusting the light quantity is connected to the control circuit through a wiring means for connecting the optical pickup and the player body. As a result, the following unique operational effects are exhibited.

Since the control circuit is provided in the player body and the semi-fixed resistor for adjusting the light amount is provided on the flexible substrate near the connector, the optical pickup can be made extremely small and lightweight. Since the optical pickup can be connected to the adjustment control circuit in advance and the semi-fixed resistor for adjusting the light amount can be adjusted, it is not necessary to perform the adjustment after it is incorporated in the player main body. Since the semi-fixed resistor for adjusting the light intensity is not directly connected to the semiconductor laser but is independent, the degree of freedom in the circuit configuration of the emitted light intensity control circuit is great. It can be easily changed to a circuit suitable for it.

[Brief description of drawings]

FIG. 1 ... Perspective view of an optical pickup and a player body substrate incorporating an embodiment of the present invention. FIG. 2 ... Circuit diagram of electric system of the optical pickup. FIG. 3 ... Circuit diagram of its APC circuit. Optical pickup 2 ... Flexible substrate, 3 ... Semi-fixed resistor 4, 6 ... Connector 5 ... Player body substrate 7 ... Semiconductor laser 8 ... Photodetector 9 ... Actuator drive coil

Claims (1)

[Scope of utility model registration request] 1. A flexible circuit board having: (a) a control circuit provided in the player body for controlling the amount of light emitted from a semiconductor laser of an optical pickup; and (b) a connector connected to the optical pickup and connected to the player body at the tip. (C) A semiconductor laser light quantity adjusting device for an optical pickup, comprising: a semi-fixed resistor for light quantity adjustment, which is provided on a flexible substrate near the connector and is connected to the control circuit via the connector.