JP2002015475A - Master optical disk exposing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a master optical disk exposing device capable of preventing a human body from being irradiated with a scattered light, providing a space for enabling a human hand to reach an optical element in order to adjust the position of the optical element, and making the optical adjustment of the master optical disk exposing device without irradiating the human body with the laser beam of a harmful wave length of 400 nm or lower. SOLUTION: In an optical adjusting area for adjusting the optical element of the master disk exposing device, a shielding-off means is provided for shielding off a scattered light from an exposure light source.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk master exposure apparatus for irradiating an exposure pattern onto a master of an optical disk coated with a photoresist with light from an exposure light source, for example, a laser beam.

[0002]

2. Description of the Related Art As an exposure light source of a conventional mastering apparatus for cutting a master of an optical disk, a continuous wave gas laser such as a Kr laser having a wavelength of about 413 nm has been used as an exposure light source.

[0003]

The effect of the conventional laser light on the human body is due to its high energy density. If the human body is directly irradiated with high-power laser light, damage to human body tissue may occur. Was to occur. However, with the increase in the density of optical discs, a Kr laser that oscillates ultraviolet light with a wavelength of 351 nm and a laser that oscillates deep UV with a wavelength of 266 nm have come to be used as an exposure light source for a mastering device. It has been found that such short-wavelength laser light causes damage to human tissues because individual photons have high energy even if they are scattered light.

In the conventional optical disk master exposure apparatus, safety measures such as attaching a cover to the master exposure apparatus so as to prevent laser light from leaking to the outside and performing fine adjustment of the position of some optical elements by remote control are provided. Has been done.
However, when assembling the optical system from the beginning, a method is used in which humans arrange optical elements one by one with respect to the laser light of the exposure light source. In this case, direct light or scattered light of the laser is Is very likely to be irradiated.

Accordingly, the present invention has been made in view of the above-mentioned circumstances, and has been developed in a master disc exposure apparatus which uses a laser beam having a wavelength of 400 nm or less to realize safety for a human body. The purpose is to provide a device.

[0006]

In order to solve the above-mentioned problems, the present invention provides an exposure light source having a wavelength of 400 nm or less, means for condensing light from the exposure light source on an optical disk master, and an optical disk master. An optical disc master exposure apparatus having means for moving a focused spot relatively in the radial direction from the center of rotation while rotating the lens at a controlled rotation speed, and an optical element for adjusting light from the exposure light source , An optical disk master exposure apparatus is provided, wherein a shielding means for shielding scattered light from the exposure light source is provided in an optical adjustment area near the optical element.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an optical disk master exposure apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an embodiment of an optical disk master exposure apparatus of the present invention, FIG. 2 is a diagram showing an example of a light shielding plate, and FIG. 3 is a diagram showing another example of a light shielding plate.

As shown in FIG. 1, light from an exposure light source 10 is incident on an electro-crystal optical element 11 for adjusting the light intensity, and then reflected by a mirror 12 at 90 degrees to generate an electric pulse signal corresponding to data. The light enters a modulator 13 that switches at high speed and modulates the light intensity. The modulated light is reflected again by 90 degrees by the mirror 14, the beam diameter is expanded by the beam expander 15, then reflected vertically by the mirror 17, passes through the objective lens 18, and is coated with a photoresist in advance. The optical disc master 19 is focused.

Optical elements are arranged along the optical system of the exposure apparatus shown in FIG. 1 and optical adjustment areas 11A, 12A, 13A, 14A, 15A, and 1A for adjusting the optical elements.
6A and 17A are provided. Optical adjustment area 11A, 12
The optical elements adjusted by A, 13A, 14A, 15A, 16A, and 17A include, for example, an electro-optic crystal element 11, a mirror 12, a modulator 13, a mirror 14, an expander 15, a beam, as shown in FIG. There are a splitter 16, a mirror 17, an objective lens 18, and the like.

Next, with reference to FIGS. 2 and 3, a method of adjusting the modulator 13 will be described as an example of the adjustment of the optical element in the optical adjustment use area. First, gloves capable of sufficiently attenuating the laser intensity are worn in order to avoid direct irradiation of the laser beam to the hand, since the human directly places the optical component by hand. Further, since ultraviolet rays cannot be recognized by the naked eye, an adjusting plate 21 coated with, for example, a fluorescent paint is arranged behind a place where the optical components are to be arranged, and the optical element is arranged while confirming the position where the fluorescent light is emitted.

Here, in order to avoid irradiating the human body with stray light and scattered light generated during the adjustment, the shielding means 13 shown in FIG.
As B, for example, a shielding plate (acrylic plate) 22 is arranged. This acrylic is opaque to ultraviolet light and has sufficient transmittance for fluorescence. At the time of adjustment, for example, an optical element such as the modulator 13 is adjusted from the side of the acrylic plate. Therefore, the scattered light emitted from the exposure light source is shielded by the shield plate 22, so that the light does not reach the adjuster who works in the optical adjustment area.

When an area where scattered light is generated is wide, an adjustment hole 24 provided with a plurality of arc-shaped rubbers is provided on an acrylic plate having a large shielding area so as to prevent the scattered light from leaking, as shown in FIG. A shielding plate 23 is used.

As the shielding means, the electro-optic crystal element 1
1, a mirror 12, a modulator 13, a mirror 14, an expander 15, a beam splitter 16, a mirror 17, and an optical adjustment area 11A in the vicinity where the objective lens 18 is arranged.
In 2A, 13A, 14A, 15A, 16A, 17A,
Shielding means 11B, 12B, 13B, 14B, 15B, 1
6B and 17B are arranged. Shielding means 11B, 12
B, 13B, 14B, 15B, 16B, and 17B are examples of the shield plate 22 shown in FIG. 2 or 3 described above.

The above-mentioned shielding means not only prevents the scattered light from being emitted to the human body, but also provides a space where a human hand can reach the optical element in order to adjust the position of the optical element. According to the present invention, the optical adjustment of the master exposure apparatus can be performed without receiving the laser beam having a wavelength of 400 nm or less which is harmful to the human body.

[0015]

As described above, there is an advantage that the scattered light from the exposure light source can be prevented from irradiating the human body and the exposure apparatus can be prevented from being adversely affected.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of an optical disk master exposure apparatus of the present invention.

FIG. 2 is a diagram illustrating an example of a light shielding plate.

FIG. 3 is a diagram showing another example of the light shielding plate.

[Explanation of symbols]

10. Exposure light source 11. Electro-optical crystal element 12, 14, 17, Mirror 13, Modulator 15, Beam expander 16, Beam splitter 18, Objective lens 19, Optical disk master 20, Light Detection element 11A, 12A, 13A, 14A, 15A, 16A, 17A
・ Optical adjustment area 11B, 12B, 13B, 14B, 15B, 16B, 17B
・ Shielding means 21 ・ ・ Adjustment plate 22,23 ・ ・ Shielding plate 24 ・ ・ Adjustment hole

Claims (2)

[Claims] 1. An exposure light source having a wavelength of 400 nm or less, means for condensing light from the exposure light source on an optical disk master, and rotating the condensed spot while rotating the optical disk master at a controlled rotation speed. In an optical disk master exposure apparatus having means for relatively moving from the center in the radial direction, and an optical element for adjusting light from the exposure light source, an optical adjustment area near the optical element includes an optical adjustment area from the exposure light source. An optical disk master exposure apparatus, comprising a shielding means for shielding scattered light. 2. The optical disk master exposure apparatus according to claim 1, wherein said shielding means is transparent for light in a visible region and is opaque for light having a wavelength of 400 nm or less.