JPH05107405A - Optical component - Google Patents

Abstract

PURPOSE:To make an optical component free from dust and to prevent dust from sticking to the same by charging a conductive thin film with a positive or negative potential by a charge feed means. CONSTITUTION:A conductive thin film 4 is applied over a surface part of an optical component body 5 which may transmits or reflect a light beam. The conductive thin film 4 is connected thereto with a voltage drive circuit 3 serving as a charge feed means. Further, a controller 2 delivers a control signal indicating an applied voltage pulsative period and an applied voltage value in accordance with a clock signal, to the voltage drive circuit. Further. the voltage drive circuit 3 delivers an applied voltage in accordance with the control signal to the conductive thin film 4. That is, the conductive thin film 4 is charged with a positive and/or negative potential. Accordingly, when it has a charged polarity opposite to the charged polarity of dust sticking to the surface part of the conductive thin film 4, the dust is separated therefrom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to optical parts such as lenses and prisms.

[0002]

2. Description of the Related Art Conventionally, optical parts such as lenses, prisms or mirrors have been used in various technical fields. These optical components are made of a transparent material such as a glass material and have a predetermined shape. These optical components refract and / or reflect a light beam when the light beam is incident on the optical component to converge or diffuse the light beam, or
It is deflected to produce a desired optical effect.

[0003]

By the way, in the above-mentioned optical component, in order to facilitate the manufacturing, reduce the weight, etc., a synthetic resin material is used instead of the conventional glass material. Is proposed. Further, with regard to this optical component, an extremely small one has come to be used with the miniaturization of various devices configured using the optical component.

Most of the synthetic resin materials are more likely to be charged with static electricity than the glass materials. Therefore, dust is likely to adhere to the optical component formed of the synthetic resin material due to charging. When dust adheres, the light transmittance is reduced, and the light flux is diffracted and absorbed by the dust.
There is a possibility that the desired optical effect may not be obtained.

Conventionally, dust adhering to optical components has been removed by regular cleaning work or the like. However,
It is difficult to perform the cleaning work without damaging the optical component, and particularly in a downsized optical component, it is extremely difficult to remove dust once attached to the optical component from the optical component. Has become.

Therefore, the present invention is proposed in view of the above situation, and an object thereof is to provide an optical component in which dust is prevented from adhering to at least a surface portion through which a light beam is transmitted and / or reflected. And

[0007]

In order to solve the above problems and achieve the above object, an optical component according to the present invention is an optical component main body formed of a transparent material, and at least a luminous flux of the optical component main body. It is provided with a conductive thin film deposited on the surface part through which the light passes and / or is reflected, and a charge supply means for charging the conductive thin film to a positive potential and / or a negative potential.

[0008]

In the optical component according to the present invention, the conductive thin film adhered to at least the surface portion of the optical component body formed of the transparent material through which the light flux passes and / or is reflected,
Since the electric charge is supplied to the positive potential and / or the negative potential by the electric charge supplying means, the dust is separated when the dust attached to the surface of the conductive thin film is charged to the opposite polarity.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings. INDUSTRIAL APPLICABILITY The optical component according to the present invention is used as a component constituting various optical devices such as an optical pickup device, a microscope, a telescope, etc. constituting a recording and / or reproducing device for an optical information signal recording medium. is there. As shown in FIG. 1, this optical component has an optical component body 5 formed of a transparent material such as various glass materials and synthetic resin materials in a predetermined shape. The optical component body 5 is formed as a lens, a prism, or a mirror, and refracts and / or reflects an incident light beam to converge, diffuse or deflect the light beam. It is formed to have an effect.

Then, a surface portion of the optical component main body 5 on which the light flux is incident and which transmits or reflects the light flux is
The conductive thin film 4 is deposited and formed. This conductive thin film 4
Is formed to have optical transparency by depositing a metal oxide such as indium or tin on the surface of the optical component body 5 by means of vapor deposition, sputtering or the like. Has been done.

A voltage drive circuit 3 which constitutes a charge supply means is connected to the conductive thin film 4. The charge supply means includes a clock 1, a controller 2 supplied with a clock signal from the clock 1, and the controller 2.
The power supply drive circuit 3 is supplied with a more control signal.

The clock 1 is composed of an oscillator, generates a clock signal having a predetermined cycle, and supplies it to the controller 2. The controller 2 generates a control signal instructing an applied voltage pulsation cycle and an applied voltage value based on the clock signal, and supplies the control signal to the voltage drive circuit 3. Based on the control signal, the voltage drive circuit 3 generates an pulsating applied voltage having a predetermined cycle, a predetermined waveform and a predetermined voltage level. This applied voltage is applied to the conductive thin film 4.

That is, the potential of the conductive thin film 4 is changed according to the applied voltage applied by the voltage drive circuit 3.
Pulsatingly fluctuates.

The change in the potential of the conductive thin film 4 is shown in FIG. 2, which is a sawtooth wave having a predetermined cycle and a predetermined level. The fluctuation of the voltage level of the sawtooth wave may be over a positive potential and a negative potential across the ground level, or may be always at the positive potential or always at the negative potential. But it's okay.

Then, on the surface of the conductive thin film 4, when the potential of the conductive thin film 4 changes abruptly, dust attached to the surface of the conductive thin film 4 becomes dusty. It is separated from 4 and removed. In many cases, the dust is originally charged to a positive potential or a negative potential, and when the potential of the conductive thin film 4 changes, the conductive thin film 4 and the dust are charged to the same polarity. This is because an electromagnetic repulsive force occurs due to the occurrence of a moment.
The dust separated from the conductive thin film 4 in this manner includes pieces of fiber material such as cloth, paper, and hair, and metal powder.

Removal of the dust by applying a voltage to the conductive thin film 4 can be performed before the use of an optical device including this optical component. For example, when the optical device is the optical pickup device, it can be performed prior to the start of the recording and / or reproducing operation of the information signal on the information signal recording medium. Further, the removal of the dust may be performed periodically every predetermined period regardless of the usage status of the optical device.

In the optical component according to the present invention, the fluctuation of the electric potential of the conductive thin film 4 is not limited to that shown in the above-mentioned embodiment, but it changes in a sawtooth shape as shown in FIG. However, it may be converged to the ground level.
The fluctuation of the voltage level in this case is such that the amplitude gradually decreases based on the control signal generated by the controller 2. In this case, when the removal of the dust is completed, the potential of the conductive thin film 4 is set to the ground level, and the subsequent suction of dust is prevented.

Further, in the optical component according to the present invention,
The fluctuation of the electric potential of the conductive thin film 4 is as shown in FIG.
It may be changed in a rectangular wave shape. Further, the variation of the potential of the conductive thin film 4 may be converged to the ground level while varying in a rectangular wave shape as shown in FIG.

[0019]

As described above, in the optical component according to the present invention, the conductive thin film adhered and formed on at least the surface portion of the optical component body formed of the transparent material through which the light flux passes and / or is reflected. , And is charged to a positive potential and / or a negative potential by the charge supply means.

Therefore, when the conductive thin film is charged with a polarity opposite to the charge polarity of the dust attached to the surface of the conductive thin film, the dust is separated.

That is, the present invention can provide an optical component in which dust is prevented from adhering to at least a surface portion through which a light beam is transmitted and / or reflected.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an optical component according to the present invention.

FIG. 2 is a waveform diagram showing a voltage that is a sawtooth wave applied to a conductive thin film in the optical component.

FIG. 3 is a waveform diagram showing a sawtooth wave applied to a conductive thin film in the optical component and showing a voltage converged to a ground level.

FIG. 4 is a waveform diagram showing a voltage that is a rectangular wave applied to a conductive thin film in the optical component.

FIG. 5 is a waveform diagram showing a rectangular wave applied to the conductive thin film in the optical component and showing a voltage converged to the ground level.

[Explanation of symbols]

 1 --- Clock 2 --- Controller 3 ...- Voltage drive circuit 4-- ........ Conductive thin film 5 ......... Main body of optical components

Claims (1)

[Claims] 1. An optical component main body formed of a transparent material, a conductive thin film adhered to at least a surface portion of the optical component main body through which a light flux passes and / or is reflected, and the conductive thin film is a positive electrode. An optical component comprising: a charge supply unit that is charged to a potential and / or a negative potential.