Optical element

Abstract

Disclosed is an optical element that has high quality with respect to heat resistance and light resistance, as well as high quality with respect to light transmittance. The optical element includes a thermosetting resin and fine particles, and difference between refractive index of the thermosetting resin n1 and refractive index of the fine particles n2, |n1−n2| satisfies a condition of 0≦|n1−n2|≦0.1.

Description

BREIF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not intended as a definition of the limits of the scope of the invention, and wherein:

FIG. 1 is a plan view showing a schematic structure of an optical pickup device;

FIG. 2 is a plan view showing an optical surface of an object lens;

FIGS. 3A and 3B are longitudinal sectional views showing a precise structure;

FIGS. 4A and 4B are longitudinal sectional views showing a precise structure; and

FIGS. 5A and 5B are longitudinal sectional views showing a precise structure.

Claims

1. An optical element, comprising: a thermosetting resin; andfine particles, whereindifference between refractive index of the thermosetting resin n1 and refractive index of the fine particles n2, |n1−n2| satisfies a condition of 0≦|n1−n2|≦0.1.

2. The optical element of claim 1, wherein the difference between the refractive index of the thermosetting resin n1 and the refractive index of the fine particles n2, |n1−n2| satisfies a condition of |n1−n2|=0.

3. The optical element of claim 1, wherein the fine particles are inorganic oxide.

4. The optical element of claim 1, wherein mean particle diameter of the fine particles is approximately 1-100 nm.

5. The optical element of claim 1, wherein the thermosetting resin is a resin selected from a group consisting of silicone resin, allyl ester resin, acrylate resin, and epoxy resin.

6. The optical element of claim 5, wherein the thermosetting resin is silicon resin.

7. The optical element of claim 6, wherein the silicone resin is represented by the following general formula (1), ((R1)(R2)SiO2)m  (1)wherein in the aforementioned general formula (1), R1 and R2 indicate the same or different mono-valent hydrocarbon groups, the mono-valent hydrocarbon groups being substituted or non-substituted, and m indicates integer number of 50 or larger.