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CN-122010406-A - Optical glass

CN122010406ACN 122010406 ACN122010406 ACN 122010406ACN-122010406-A

Abstract

The invention provides an optical glass which has excellent light transmittance characteristics and devitrification resistance in the visible region and has high refractive index characteristics. The optical glass is characterized by comprising 3-18% by mass of SiO 2 , 5-11.5% by mass of B 2 O 3 , 0-7% by mass of Al 2 O 3 , 0-11% by mass of CaO, less than 1% by mass of ZnO, 7-20% by mass of TiO 2 , 3-38% by mass of Nb 2 O 5 , 27-49.8% by mass of La 2 O 3 , 6-14% by mass of Gd 2 O 3 , 0-5% by mass of Y 2 O 3 , less than 6% by mass of Ta 2 O 5 , less than 0.6% by mass of WO 3 , and 1-2 by mass of B 2 O 3 /SiO 2 .

Inventors

  • KONOSHITA SATOKO
  • MATANO TAKAHIRO

Assignees

  • 日本电气硝子株式会社

Dates

Publication Date
20260512
Application Date
20200626
Priority Date
20190705

Claims (10)

  1. 1. An optical glass is characterized by comprising, by mass%, from 2.2 to 5% of La 2 O 3 27%～49.8%、Y 2 O 3 and, by mass%, from 0.084 to 0.3 of Y 2 O 3 /Ln 2 O 3 .
  2. 2. The optical glass according to claim 1, wherein the glass composition contains 3 to 18% of SiO 2 、B 2 O 3 、TiO 2 、Nb 2 O 5 and 3 to 11.5% of Gd 2 O 3 ,SiO 2 , and 5 to 11.48% of B 2 O 3 .
  3. 3. The optical glass according to claim 2, wherein the optical glass contains, by mass%, tiO 2 7%～20%、Nb 2 O 5 3%～38%、Gd 2 O 3 % to 14%.
  4. 4. The optical glass according to claim 3, wherein the glass contains, by mass%, 0 to 7% of Al 2 O 3 , 0 to 11% of CaO, 1% or less of Zn O, less than 6% of Ta 2 O 5 , and 0.6% or less of WO 3 , and wherein B 2 O 3 /SiO 2 is 1 to 2 in mass%.
  5. 5. The optical glass according to any one of claims 1 to 4, wherein the optical glass contains Ln 2 O 3 % by mass or more, wherein Ln is at least one selected from La, gd, Y, and Yb.
  6. 6. The optical glass according to any one of claims 1 to 4, wherein the optical glass contains BaO in mass% of 0 or more and less than 0.2%.
  7. 7. The optical glass according to any one of claims 1 to 4, wherein the refractive index (nd) is 1.84 to 2.04.
  8. 8. The optical glass according to any one of claims 1 to 4, wherein the liquid phase temperature is 1150 ℃.
  9. 9. The optical glass according to any one of claims 1 to 4, wherein the linear transmittance at a wavelength of 500nm and a thickness of 5mm is 72% or more.
  10. 10. An optical element comprising the optical glass according to any one of claims 1 to 9.

Description

Optical glass The application is a divisional application of PCT/JP2020/025264 with the application number 202080036519.9 and the application date 2020.6.26 and the application name of 'optical glass'. Technical Field The present invention relates to an optical glass used for optical elements such as lenses. Background For example, in wearable devices such as glasses with projectors, glasses-type or goggle-type displays, virtual reality or augmented reality display devices, and virtual image display devices, glass materials are used as optical elements such as lenses. The glass material is required to have high refractive index characteristics in view of wide angle, high brightness and high contrast of an image, improvement of light guiding characteristics, and the like. In addition, in applications such as in-vehicle cameras and visual sensors for robots, small-sized imaging glass lenses having a wide imaging angle of view are used (for example, refer to patent document 1). Such an imaging glass lens is also required to have high refractive index characteristics. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2015-74572 Disclosure of Invention Problems to be solved by the invention However, conventionally, in the case of producing a glass composition having a high refractive index, an element having an absorption in the visible region is often used as a component for increasing the refractive index. Therefore, in general, high refractive index glass has a problem of low light transmittance in the visible region. In addition, when a glass composition having a high refractive index is produced, the components constituting the glass skeleton tend to be reduced. Therefore, the high refractive index glass is generally prone to devitrification and has a problem of poor mass productivity. In view of the above, an object of the present invention is to provide an optical glass having excellent light transmittance characteristics and devitrification resistance in the visible region and having high refractive index characteristics. Technical proposal As a result of the studies conducted by the present inventors, it was found that the above problems could be solved by containing a high refractive index component such as TiO 2、Nb2O5、La2O3、Gd2O3 and strictly limiting the content of SiO 2 and B 2O3 contributing to the vitrification stability. Specifically, the optical glass of the present invention is characterized by containing 3 to 18% by mass of SiO 2, 5 to 11.5% by mass of B 2O3, 0 to 7% by mass of Al 2O3, 0 to 11% by mass of CaO, 1% or less of ZnO, 7 to 20% by mass of TiO 2, 3 to 38% by mass of Nb 2O5, 27 to 49.8% by mass of La 2O3, 6 to 14% by mass of Gd 2O3, 0 to 5% by mass of Y 2O3, less than 6% by mass of Ta 2O5, 0.6% by mass of WO 3, and 1 to 2 by mass of B 2O3/SiO2. Preferably, the optical glass of the present invention contains 36% by mass or more of Ln 2O3 (where Ln is at least one selected from La, gd, Y, and Yb). Preferably, the optical glass of the present invention contains 0% or more and less than 0.2% by mass of BaO. Preferably, the refractive index (nd) of the optical glass of the present invention is 1.84 to 2.04. Preferably, the liquid phase temperature of the optical glass of the present invention is 1150 ℃. The optical glass of the present invention preferably has a linear transmittance of 72% or more at a wavelength of 500nm and a thickness of 5 mm. The optical element of the present invention is characterized by comprising the optical glass. Advantageous effects According to the present invention, an optical glass having excellent light transmittance characteristics in the visible region and resistance to devitrification and having high refractive index characteristics can be provided. Detailed Description The optical glass is characterized by comprising 3-18% by mass of SiO 2, 5-11.5% by mass of B 2O3, 0-7% by mass of Al 2O3, 0-11% by mass of CaO, less than 1% by mass of ZnO, 7-20% by mass of TiO 2, 3-38% by mass of Nb 2O5, 27-49.8% by mass of La 2O3, 6-14% by mass of Gd 2O3, 0-5% by mass of Y 2O3, less than 6% by mass of Ta 2O5, less than 0.6% by mass of WO 3, and 1-2 by mass of B 2O3/SiO2. The reason why the glass composition is limited in this way will be described below. In the following description of the content of each component, "%" means "% by mass" unless otherwise specified. SiO 2 is a glass skeleton component, and is a component for improving vitrification stability and chemical durability. The content of SiO 2 is 3 to 18%, preferably 3.5 to 15%, 4 to 12%, particularly preferably 5 to 10%. If the content of SiO 2 is too small, the above-mentioned effects are not easily obtained. On the other hand, if the content of SiO 2 is too large, the refractive index tends to be lowered. B 2O3 is a component contributing to vitrification stability. The content of B 2O3 is 5% to 11.5%, preferably 6.5% to 11.5%, 7% to 11%, 8% to 10.5%, particula