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

Objective lens and optical pickup device

A technology of optical pickup device and objective lens, which is applied in the direction of optics, condenser lens, optical elements, etc., and can solve problems such as the inability to measure the inclination of the objective lens

Active Publication Date: 2016-07-06
KONICA MINOLTA INC
View PDF7 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] However, the present inventors designed and tried to manufacture an objective lens with high NA (the image side numerical aperture is more than 0.7 and less than 0.9) which has gradually become the mainstream in recent years. As a result, the inclination of the objective lens on the optical pickup cannot be adjusted smoothly. measure such problems

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
  • Objective lens and optical pickup device
  • Objective lens and optical pickup device
  • Objective lens and optical pickup device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0364] Figure 11 It is a sectional view of the objective lens 2a of Example 1. Figure 11 The objective lens 2a of the shown embodiment 1 is a plastic single-piece lens, which has a first optical surface 25 disposed facing the light source and a second optical surface 26 facing the first optical surface with a larger curvature than the first optical surface. An optical disc is arranged on the second optical surface 26 side.

[0365] Although not shown in figure, the optical path difference providing structure is formed in the 1st optical surface 25. As shown in FIG. The optical path difference imparting structure is a ring-shaped diffractive structure, and has a function of correcting spherical aberration caused by temperature change.

[0366] The numerical aperture of this objective lens 2a is 0.85, and it is a dedicated objective lens for BD corresponding to the laser beam of wavelength 405nm.

[0367] As shown in Table 1, the A / B value of the objective lens 2a is 0.26, ...

Embodiment 2

[0380] Figure 12 It is a sectional view of the objective lens 2b of Example 2. Figure 12 The objective lens 2b shown is a plastic single-lens lens having an optical path difference imparting structure substantially the same in shape as in Example 1, and the A / B value is changed.

Embodiment 3

[0382] Figure 13 It is a sectional view of the objective lens 2c of Example 3. Figure 13 The objective lens of Example 3 shown is a plastic single-piece lens. The 1st optical surface 25 of the objective lens 2c of Example 3 is an aspherical shape which does not have an optical path difference providing structure.

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
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

The present invention provides a high NA objective lens that can satisfactorily measure the inclination when mounted on an optical pickup device and can assemble the optical pickup device with high accuracy, and an optical pickup device provided with the high NA objective lens. The objective lens has a first optical surface formed on the light source side, a second optical surface formed to face the first optical surface and with a radius of curvature larger than the first optical surface, and is located outside the second optical surface when viewed from the optical axis direction and is in contact with the second optical surface. The end surface is a plane that is approximately perpendicular to the optical axis. The image side numerical aperture (NA) is 0.7 or more and 0.9 or less. As a straight line passing through the optical axis and the end surface when viewed from the optical axis direction, let the distance of the straight line within the end surface range be A (mm ), when the distance from the optical axis to the straight line at the outermost peripheral portion of the end face is B (mm), the following equation (1) is satisfied, that is, 0.12<A / B<0.5 (1).

Description

technical field [0001] The present invention relates to an objective lens and an optical pick-up device, in particular to an objective lens and an optical pick-up device which can more suitably adjust the inclination when the objective lens is assembled on the optical pick-up device. Background technique [0002] In recent years, in the optical pickup device, the laser light source used as a light source for reproducing information recorded on the optical disc and recording information on the optical disc has been shortened. Laser light sources are becoming more and more practical. When using these blue-violet laser light sources, in the case of using an objective lens with the same numerical aperture (NA) as DVD (Digital Versatile Disc), it is possible to record 15 to 20 GB of information on an optical disc with a diameter of 12 cm, while increasing the NA of the objective lens When it reaches 0.85, information of 23-25 ​​GB can be recorded on a disc with a diameter of 12 ...

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 Patents(China)
IPC IPC(8): G11B7/1374G11B7/1353G02B19/00
CPCG11B7/1374G02B19/0076G11B7/1353
Inventor 水町靖荻原贤治
Owner KONICA MINOLTA INC
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