JPH07201082A - Optical disk inspecting device - Google Patents

Abstract

PURPOSE:To improve the reliability of a measuring result and to obtain a stable and high quality by controlling the atmospheric temperature of an optical disk to be inspected and keeping air in the atmosphere clean. CONSTITUTION:A temperature sensor 11 provided in an inspecting drive 1 detects temperature therein and a temperature controller adjusts the temperature of air supplied to the inspecting drive 1 so as to allow a temperature in the inspecting drive 1 to be kept at a prescribed temperature at all times based on this temperature detecting signal. Thus, even when ambient temperature around the inspecting drive 1 changes, no error is generated in an inspecting result such as recording sensitivity of an optical disk 2. Also, only by adding a temperature controller and an air cleaner to a conventional optical disk inspecting device, an optical disk stable and high in quality can be manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection device for evaluating various characteristics of an optical disc, and more particularly to a technique for improving the reliability of the measurement result.

[0002]

2. Description of the Related Art Optical discs are used as external recording media for computers and recording media for music. For evaluating various characteristics of the optical discs, such as reflectance, signal strength, error rate, and recording sensitivity. As a device
There is an optical disk inspection device. In general, an optical disk inspection apparatus evaluates the characteristics of an optical disk by irradiating the optical disk with laser light from the optical head to record and reproduce signals. The recording sensitivity of an optical disk is an extremely important evaluation item because the recording of a signal on an optical disk is performed by utilizing the heat of laser light.

However, if the ambient temperature changes and the temperature of the optical disk changes, a large error occurs in the measurement result of the recording sensitivity. FIG. 3 shows an example of the characteristics of the ambient environment temperature and the recording sensitivity in the case of a magneto-optical disk. The recording sensitivity changes by about 0.04 mW when the disk temperature changes by 1 ° C. The conventional optical disc inspection apparatus is provided with a means for sucking the outside air to dissipate and cool the inside of the inspection drive, but the function to keep the temperature inside the inspection drive constant and control the temperature of the disc to be inspected Is not provided.

Further, even if the intensity of the laser beam emitted from the optical head deviates from the specified value, the measurement results such as recording sensitivity and reflectance cannot be obtained correctly. In a normal use environment, the intensity of laser light emitted from the optical head tends to decrease with use time due to contamination of optical elements such as an objective lens and a beam splitter in the optical head. In the conventional optical disc inspection apparatus, there is no means for preventing the optical element in the optical head from being soiled.

[0005]

As described above, in the conventional optical disc inspection apparatus, the environmental temperature around the inspection apparatus is changed and the emission laser power is reduced due to the contamination of the optical element in the optical head. If an error occurs in the measurement result such as recording sensitivity or reflectance, the characteristics of the optical disc are adjusted in the wrong direction. As a result, when information is recorded / reproduced on / from the optical disc by the optical disc device, a trouble such as signal recording or reproduction failure may occur.

The present invention has been made to solve the above problems, and prevents contamination of the optical elements in the optical head and keeps the temperature of the optical disc to be inspected at a predetermined temperature to obtain accurate measurement results. It is an object of the present invention to provide an optical disc inspection device capable of obtaining the following.

[0007]

In order to achieve the above object, the present invention provides an optical disc inspection apparatus for irradiating a light beam on an optical disc to record / reproduce signals to evaluate various characteristics of the optical disc. An optical disc to be set is set, and an inspection compartment for irradiating the optical beam emitted from the optical head onto the optical disc to record / reproduce signals, and a temperature for adjusting the ambient temperature in the inspection compartment to a predetermined temperature It is provided with an adjusting means, an air cleaning means for keeping the air in the inspection compartment clean, and a measuring means for processing the signal reproduced by the optical head to obtain characteristic data of the optical disk.

[0008]

According to the above construction, the atmosphere temperature in the inspection compartment in which the optical disk to be inspected is set is adjusted to a predetermined temperature, the temperature of the optical disk is maintained at a predetermined temperature, and the air in the atmosphere is cleaned. Therefore, the measured value of the recording sensitivity of the optical disc does not have an error due to the environmental temperature change, and the optical head is not contaminated, and a stable light beam output can be obtained for a long period of time. As a result, the measurement data of the optical disc becomes accurate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an optical disc inspection apparatus according to an embodiment of the present invention. In FIG. 1, an inspection drive 1 is an inspection compartment in which an optical disc 2 to be inspected is set, and a spindle motor 3 that drives the optical disc 2 to rotate and a light beam is emitted to the optical disc 2 to record or reproduce a signal. It is provided with an optical head 4 and the like.
The measuring device 5 processes the signal reproduced by the optical head 4 and calculates characteristic data values such as signal strength, error rate, and reflectance.

The inspection drive 1 is provided with a mechanism for adjusting the internal ambient temperature to a predetermined temperature.
The mechanism is composed of a temperature controller 6, a blower fan 7, a filter 8 and the like. The temperature controller 6 controls the temperature of the outside air sucked by the blower fan 7, and the temperature-controlled air is passed through a filter 8 to an intake port 9 Sent into the inspection drive 1 from
Dissipates heat and cools the inspection drive 1. Inspection drive 1
The outside air sent to the air is discharged from the exhaust port 10. The temperature sensor 11 detects the temperature inside the inspection drive 1 and returns the detection signal to the temperature controller 6. The intake port 9 and the exhaust port 10 are provided on opposite side walls of the inspection drive 1.

In the above structure, the temperature sensor 11 installed in the inspection drive 1 detects the temperature in the inspection drive 1, and the temperature controller 6 always determines the temperature in the inspection drive 1 based on the detected temperature signal. The temperature of the air sent into the inspection drive 1 is adjusted so that the temperature becomes. As a result, even if the environmental temperature around the inspection drive 1 changes, the inspection result such as the recording sensitivity of the optical disk 2 does not have an error. Further, the air sent for heat dissipation and cooling in the inspection drive 1 is cleaned by passing through the filter 8 and the cleanliness of the air can be maintained, so that optical elements such as the objective lens in the optical head 4 are contaminated. And the decrease in emitted laser power with time is greatly improved. Since the air ventilated in the inspection drive 1 flows substantially parallel to the plane of the optical disc 2, the heat radiation from the spindle motor 3 and the optical head 4 is less likely to affect the atmosphere of the optical disc 2.

FIG. 2 shows the change of the output laser power with respect to the operating time of the inspection apparatus in one embodiment of the present invention. From the figure, it can be seen that according to the present embodiment, the deterioration with time is suppressed to be smaller than that of the conventional optical disc inspection apparatus. The present invention is not limited to the configuration of the above-described embodiment, and various modifications can be made. For example, any air conditioning means can be used to keep the inside of the inspection drive 1 at a predetermined temperature.

[0013]

As described above, according to the present invention, the atmospheric temperature of the optical disk to be inspected is controlled to a predetermined temperature, and the air in the same atmosphere is kept clean. Since there is no error and a stable light beam power can be obtained for a long period of time, an accurate optical disc measurement result can be obtained. Moreover, the reliability of the measurement results of the optical disc inspection device can be greatly improved by simply adding a simple configuration of temperature control and air cleaning to the conventional optical disc inspection device, and a stable and high-quality optical disc is created. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an optical disc inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing changes over time in emitted laser power of the optical disc inspection apparatus according to the present embodiment and the conventional example.

FIG. 3 is a characteristic diagram showing measurement results of ambient temperature and recording sensitivity of an optical disc inspection device in a conventional example.

[Explanation of symbols]

 1 Inspection drive (compartment for inspection) 2 Optical disk 4 Optical head 5 Measuring equipment 6 Temperature controller 7 Blower fan 8 Filter

Claims (1)

[Claims] 1. An optical disc inspection apparatus for irradiating an optical disc with a light beam to record / reproduce signals to evaluate various characteristics of the optical disc. An optical disc to be inspected is set and a light beam emitted from an optical head. An inspection compartment for irradiating the optical disc to record / reproduce signals, temperature adjusting means for adjusting the ambient temperature in the inspection compartment to a predetermined temperature, and clean air in the inspection compartment. An optical disk inspecting apparatus comprising: an air cleaning unit for performing the above operation; and a measuring unit for processing a signal reproduced by the optical head to obtain characteristic data of the optical disk.