JPH04170727A - Optical information recording and reproducing device - Google Patents

Abstract

PURPOSE:To accurately detect the contamination on an information recording carrier and on the lens for an optical head by a method wherein, before information is recorded on and reproduced from the information recording carrier. A light flux used to record and reproduce the information is converged on the surface of a substrate for the information recording carrier. CONSTITUTION:Before information is recorded and reproduced, a light flux 5 is converged on the surface of an optical disk 2, and the contamination on the surface of the disk 2 is detected by using a contamination detection circuit 4. When the light flux 5 is converged on the surface of the disk 2, a focusing error signal is detected by using a focusing servo circuit 3. The amplitude of the focusing error signal is changed by a reflection factor on a face on which the light flux 5 is being converged, and becomes definite on the surface of the disk irrespective of the reflection factor of a recording film. As a result, it becomes definite irrespective of the disk as long as the material for a substrate is the same. Consequently, when the amplitude of the focusing error signal is detected by using the circuit 4 and an amplitude level is judged, the contamination on the disk 2 or on the lens for an optical head 1 can be judged.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical information recording/reproducing device, and more particularly to detecting dirt on an information recording carrier and an optical head.

2. Description of the Related Art In recent years, optical information recording and reproducing devices have been commercialized as write-once optical discs and rewritable optical discs, and are applied to image files, document files, data files, and the like.

However, when these optical disk devices are used for a long period of time, dust may adhere to the surface of the optical disk or the lens of the optical head, which may cause errors when recording and reproducing information on the disk. For this reason, conventional optical disk devices attempt to detect dirt on the disk or head by detecting the reflectance of the recording portion of the optical disk or the amplitude of the recording signal.

Problems to be Solved by the Invention However, optical disk devices using the dirt detection method described above are affected by changes in the reflectance of the recording layer of the optical disk and fluctuations in the recording signal amplitude, resulting in problems with the disk and head. It was not possible to accurately detect dirt.

Therefore, if the reflectance of the optical disc is low or the recording signal amplitude is small, even the slightest stain will be detected, making it unnecessary and requiring cleaning.

On the other hand, if the reflectance is high or if the recording signal amplitude is large, dirt will not be detected, which may cause errors during recording and reproduction.

As described above, conventional optical information recording and reproducing devices are unable to accurately detect the state of lens contamination on discs and optical heads, and have the problem of preventing unnecessary reading and errors during recording and reproducing. There is.

In view of the above problems, the present invention provides an optical information recording/reproducing device that can accurately detect lens dirt on an information recording carrier and an optical head.

Means for Solving the Problems In order to solve the above problems, the optical information recording/reproducing apparatus of the present invention includes the following steps:
A light beam for recording and reproducing information is focused on the substrate surface of the information recording carrier to detect dirt on the lens of the information recording carrier and the optical head.

Function: With the above-described configuration, the present invention makes it possible to accurately detect dirt on the surface of the information recording carrier and dirt on the lens of the optical head without being affected by changes in the reflectance of the information recording carrier or fluctuations in the recording signal amplitude. do. That is, before recording and reproducing information on the information recording carrier, the substrate surface of the information recording carrier is coated with
By focusing the light beam for recording and reproducing information, it is possible to accurately detect lens dirt on the information recording carrier and the optical head, prevent errors during recording and reproducing, and avoid unnecessary leaning. In addition, when applied to conventional optical disk devices, etc., it does not require major modification, so an optical information recording and reproducing device that accurately detects dirt on the information recording carrier and the lens of the optical head can be realized easily and at low cost. can do.

Embodiments Hereinafter, embodiments of the optical information recording/reproducing apparatus of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the optical information recording/reproducing apparatus of the present invention.

In FIG. 1, 1 is an optical head, 2 is an optical disk, and 3 is an optical head.
4 indicates a focus servo circuit, and 4 indicates a dirt detection circuit.

A light beam 5 emitted from the optical head 1 is controlled by a focus servo circuit 3 to focus on the optical disk 2 to record and reproduce information. In the optical information recording and reproducing apparatus of this embodiment, before recording and reproducing information, the light beam 5 is focused on the substrate surface, and the contamination detection circuit 4 detects contamination on the disk surface.

When the light beam 5 is focused on the disk surface, the focus servo circuit 3 detects a focus error signal as shown in FIG. The amplitude F' p-p of this focus error signal changes depending on the reflectance of the surface on which the light beam 5 attempts to converge, and is constant on the disk surface regardless of the reflectance of the recording film, so if the substrate material is the same, the disk It remains constant regardless of Therefore, by detecting the amplitude F pp of this focus error signal with the dirt detection circuit 4 and determining the amplitude level, it is possible to determine whether the lens of the disk 2 or the optical head 1 is dirty.

In addition, since the optical disc 2 generally has a small recording power margin at the inner circumference and is easily contaminated near the clamp section, the optical head 1 is moved by the optical head position control circuit 6 to the vicinity of the innermost circumference position of the information recording area. By performing the above dirt determination, it is possible to more effectively prevent errors caused by disc dirt.

Effects of the Invention As described above, the present invention focuses a light beam for recording and reproducing information on the substrate surface of the information recording carrier before recording and reproducing information on the information recording carrier, thereby accurately and reproducing information. To easily detect dirt on an information recording carrier and an optical head lens.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an optical information recording/reproducing apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram showing a focus error signal waveform. 1...Optical head, 2...Optical disk, 3...Focus servo circuit, 4...
- Dirt detection circuit, 5... Luminous flux for information recording and reproduction,
6...Optical head position control circuit. Name of agent: Patent attorney Haruaki Koebi and two others 1-11 To Shisetsu, finally Figure 2

Claims (1)

[Claims] (1) An optical information recording and reproducing device that has an information recording carrier that optically records and reproduces information, and an optical head that optically records and reproduces information by irradiating the information recording carrier with a beam of light emitted from a light source. Before recording and reproducing information on the information recording carrier, the light beam is focused on the substrate surface of the information recording carrier and a reflected light signal from the surface is detected, so that the information recording carrier is , and an optical information recording/reproducing apparatus characterized by detecting lens dirt of the optical head. (2) an information recording carrier for optically recording and reproducing information, a control means for rotating the information recording carrier at a predetermined number of rotations, and an optical An optical information recording and reproducing device having an optical head for recording and reproducing information on the information recording carrier, wherein dirt on the lens of the information recording carrier or the optical head is removed from the innermost radial position of the information recording carrier to the innermost radial position where the information recording carrier can be recorded. An optical information recording/reproducing device characterized in that detection is performed within a radial position of 1/4 of the total radius from a radial position.