Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Front monitor apparatus, and optical pickup apparatus and information recording and reproducing apparatus provided with the same

A technology for an optical pickup device and a monitoring device, which is applied in the directions of recording/reproducing, optical recording head, data recording, etc. by an optical method, can solve the problems such as the inability to sufficiently reduce the howling, and achieves high-speed responsiveness and no frequency band. Narrow, good tracking effect

Inactive Publication Date: 2008-08-13
SHARP KK
View PDF1 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when the conversion efficiency from current to voltage of the front monitoring device is set to be large and the sounding occurs, the sounding cannot be sufficiently reduced.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Front monitor apparatus, and optical pickup apparatus and information recording and reproducing apparatus provided with the same
  • Front monitor apparatus, and optical pickup apparatus and information recording and reproducing apparatus provided with the same
  • Front monitor apparatus, and optical pickup apparatus and information recording and reproducing apparatus provided with the same

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0044] FIG. 1 is a schematic diagram showing the configuration of an optical pickup device 1 according to an embodiment of the present invention.

[0045] The optical pickup device 1 has a semiconductor laser element 2 as a light emitting element, a collimator lens 3, a beam splitter 4, an objective lens 5, a front monitor 6, and a semiconductor laser element driving device 12 as a light emitting element driving unit. The semiconductor laser element 2 emits laser light. The collimator lens 3 collimates the light emitted from the semiconductor laser element 2 . The beam splitter 4 reflects a part of the light emitted from the semiconductor laser element 2 and guides it to the front monitor device 6 , and transmits the rest of the light and guides it to the objective lens 5 . The objective lens 5 condenses light on the optical recording medium 7 . The objective lens 5 transmits the outward beam (outword beam) emitted from the semiconductor laser element 2 through the cover lay...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
electrical resistanceaaaaaaaaaa
electrical resistanceaaaaaaaaaa
electrical resistanceaaaaaaaaaa
Login to View More

Abstract

The invention relates to a front monitor apparatus, an optical pickup device with the front monitor apparatus, and an information record reproducing device. The invention provides a front monitor apparatus (6) which monitors a laser beam emitted from a semiconductor laser element (2) provided in the optical pickup apparatus (1), the apparatus includes first and second photodiodes (PD1, PD2) each having different light receiving sensitivity, for receiving the laser beam and outputting a current corresponding to a light receiving intensity; and a current-voltage conversion circuit (11) for differentiating voltage conversion levels for converting a current to a voltage, in association with the respective light receiving elements so that a voltage to be converted when a predetermined current is supplied from a second photodiode (PD2) having low light receiving sensitivity exceeds a voltage to be converted when the predetermined current is supplied from a first photodiode (PD1) having high light receiving sensitivity, and outputting a voltage which is obtained by conversion of a current from the respective light receiving elements.

Description

technical field [0001] The present invention relates to a front monitoring device for monitoring the intensity of laser light emitted from a light emitting element of an optical pickup device for recording, reproducing or erasing an optical recording medium, an optical pickup device having the front monitoring device, and an information recording and reproducing device. put the device. Background technique [0002] An optical pickup device forms tiny beam spots on optical recording media such as CDs and DVDs by using light beams from light emitting elements, and performs recording / reproducing or erasing of information. [0003] In an optical pickup device, when emitting laser light from a light-emitting element and reading a signal from an optical recording medium, recording a signal on an optical recording medium, and deleting a signal recorded on an optical recording medium, In order to perform these operations stably, it is necessary to keep the intensity of the laser li...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G11B7/125
CPCG11B7/1263
Inventor 福永基次
Owner SHARP KK
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com