Optical glass, optical element and process for the production thereof

A technology for optical glass and optical components, applied in glass manufacturing equipment, glass pressing, manufacturing tools, etc., to achieve good workability and suppress chromatic aberration

Inactive Publication Date: 2007-01-31
HOYA CORP
View PDF1 Cites 44 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This optical glass is light in weight and has excellent optical properties, but it cannot be said that the glass is fully satisfactory in any one of mechanical properties, thermal properties, and friction and wear

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1-10 and comparative Embodiment 1 and 2

Raw materials such as phosphates, fluorides, carbonates, nitrates, oxides, etc. were produced as needed, and the raw materials were weighed to obtain the glass compositions shown in Tables 1 and 2. Hydroxides and the like are not used since they will promote volatilization of fluorine. as B 3+ raw materials, instead of boric acid use anhydrous materials such as boron phosphate (BPO 4 ) and boric anhydride (B 2 o 3 ). In each example, the formulated raw materials were mixed and the mixture was melted in a platinum crucible. The glass in each example underwent melting at 900-1,200°C.

In each example, the glass was agitated and fined and forced to flow onto an iron plate to form a single piece. And the glass block is transferred to a furnace which has been heated to a temperature around the glass transition temperature and annealed to room temperature.

Samples for various measurements were taken from each of the glass pieces thus obtained, and their physical properties we...

Embodiment 11

[0046] A powdery mold release agent such as boron nitride or the like is uniformly applied to the surface of each glass block, each glass block is heated to soften it, and press-molded using a press mold in air. Each compression molded product has a shape obtained by adding an edge which will be removed by machining to form the optical element as a final product. The stamper products were annealed to reduce their strain, and then they were ground and polished to produce optical elements formed of the optical glasses of Examples 1-10. No defects such as polishing marks and the like were observed on the surface of each of the optical elements produced as above, and high-quality optical elements were produced. In addition, the above machining was performed without breaking any glass.

Embodiment 12

[0048] Forming glass forming materials, manufacturing glass sheets, manufacturing glass gobs, and precision press molding glass gobs can be performed by known methods.

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
Abbe numberaaaaaaaaaa
refractive indexaaaaaaaaaa
Abbe numberaaaaaaaaaa
Login to view more

Abstract

Provided are an optical glass having high-refractivity, low-dispersion and anomalous partial dispersion properties, having excellent processability, being excellent as an anomalous partial dispersion glass for suppressing chromatic aberration, containing P5+, Al3+ and alkaline earth metal ions selected from the group consisting of Mg2+, Ca2+, Sr2+ and Ba2+ as essential cationic components and F- and O2- as essential anionic components, wherein the ratio of content of Ba2+ to the total content R2+ of Mg2+, Ca2+, Sr2+ and Ba2+, Ba2+ / R2+, is 0.01 or more but less than 0.5 on the basis of cationic %, and having an Abbe's number (nud) of 68 or more, optical glass having an Abbe's number (nud) of 68 or more, a partial dispersion ratio of 0.535 or more and a frictional abrasion of 500 or less and an optical glass which is to be polished in a polishing step for producing an optical element and which is a fluorophosphate glass having a frictional abrasion of 500 or less.

Description

technical field [0001] The invention relates to optical glass, an optical element and a manufacturing method thereof. More particularly, the present invention relates to an optical glass having a high refractive index, low dispersion, and anomalous partial dispersion properties, an optical element formed from the above glass, and a method for manufacturing the optical element, the glass being suitable for use in It is used for the glass of camera or projector lens, and has excellent processability. Background technique [0002] In optical systems such as cameras etc., a design is often used for "achromaticity" in which glasses with different Abbe numbers are combined to remove chromatic aberration of the lens. Combining glasses with very different Abbe numbers can have a dramatic effect on the removal described above. In particular, secondary achromats require anomalous partial dispersion glass that has a different partial dispersion ratio than conventional optical glasses...

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): C03C3/247C03B11/00
Inventor 蜂谷洋一
Owner HOYA CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products