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US-20260126573-A1 - OPTICAL FILTER AND IMAGING APPARATUS

US20260126573A1US 20260126573 A1US20260126573 A1US 20260126573A1US-20260126573-A1

Abstract

An optical filter including a light absorbing glass substrate that absorbs light and that is composed of a phosphate-based glass or a fluorophosphate-based glass; a bonding layer that is provided on the absorbing glass substrate, that has a single layer structure, and that comprises a coupling agent composition including at least one dehydrated condensate of a silicon compound containing a Si atom; and a metal alkoxide containing a Ti atom, a Zr atom, an Al atom, or a combination thereof; and a resin layer disposed on the bonding layer.

Inventors

  • Haruna Imai
  • Shinichi Ogawa
  • Takeshi Yamazaki

Assignees

  • HOYA CORPORATION

Dates

Publication Date
20260507
Application Date
20260106
Priority Date
20180604

Claims (19)

  1. 1 . An optical filter, comprising an absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass; a bonding layer with a single layer structure; and a resin layer, wherein the resin layer is provided on the absorbing glass substrate through the bonding layer, wherein the bonding layer comprises a Si atom and one or more selected from a Ti atom, a Zr atom, and an Al atom.
  2. 2 . The optical filter according to claim 1 , wherein, in the bonding layer, a ratio of a total atomic number of a Ti atom, a Zr atom, and an Al atom to a total number of a Si atom, a Ti atom, a Zr atom, and an Al atom is greater than 0 atomic % and 33.3 atomic % or less.
  3. 3 . The optical filter according claim 1 , wherein the resin layer is provided on the absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass through a bonding layer interposed between the resin layer and the absorbing glass substrate, wherein the bonding layer comprises hydrolyzed and dehydrated condensates of one or more coupling agents selected from compounds represented by Formulas (I) and (II) below: wherein M is a Ti atom, a Zr atom, or an Al atom, R 1 , R 2 and R 3 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms, which comprise or exclude an oxygen atom or a nitrogen atom, and are equal to or different from each other, n is 4 when M is a Ti atom or a Zr atom, or 3 when M is an Al atom, a plurality of —OSiR 1 R 2 R 3 groups are equal to or different from each other, and wherein R 4 , R 5 and R 6 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms, which comprise or exclude an oxygen atom or a nitrogen atom, and are equal to or different from each other, k is a real number between 2 and 15, and a plurality of —OSiR 4 R 5 R 6 groups are equal to or different from each other.
  4. 4 . The optical filter according to claim 1 , wherein the resin layer is provided on the absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass through a bonding layer interposed between the resin layer and the absorbing glass substrate, wherein the bonding layer comprises hydrolyzed and dehydrated condensates of one or more coupling agents selected from compounds represented by Formulas (III) and (IV) below: wherein M is a Ti atom, a Zr atom, or an Al atom, R 7 , R 8 and R 9 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, n is 4 when M is a Ti atom or a Zr atom, or 3 when M is an Al atom, and a plurality of —OSi(OR 7 )(OR 8 )(OR 9 ) groups are equal to or different from each other, and wherein R 10 , R 11 and R 12 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, k is a real number between 2 and 15, a plurality of —OSi(OR 10 )(OR 11 )(OR 12 ) groups are equal to or different from each other.
  5. 5 . The optical filter according to claim 4 , wherein the coupling agent represented by Formula (III) is a reaction product between a silicon compound represented by Formula (V) below and one or more selected from metal alkoxides represented by Formulas (VI), (VII), and (VIII) below: wherein R 7 , R 8 and R 9 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 13 , R 14 , R 15 and R 16 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 17 , R 18 , R 19 and R 20 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, and wherein R 21 , R 22 and R 23 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other.
  6. 6 . The optical filter according to claim 1 , wherein the bonding layer further comprises a dehydrated condensate of silanol.
  7. 7 . The optical filter according to claim 1 , wherein the resin layer is provided on the absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass through a bonding layer interposed between the resin layer and the absorbing glass substrate, wherein the bonding layer comprises a hydrolyzed and dehydrated condensate of a coupling agent composition comprising a reaction product between 50 mol % or more and less than 100 mol % of a silicon compound represented by Formula (V) below and greater than 0 mol % and 50 mol % or less of one or more selected from metal alkoxides represented by Formulas (VI), (VII), and (VIII) below: wherein R 7 , R 8 and R 9 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 13 , R 14 , R 15 and R 16 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 17 , R 18 , R 19 and R 20 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, and wherein R 21 , R 22 and R 23 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other.
  8. 8 . The optical filter according to claim 7 , wherein the coupling agent composition is a reaction product between greater than 80 mol % and less than 100 mol % of the silicon compound represented by Formula (V) and greater than 0 mol % and less than 20 mol % of one or more metal alkoxides selected from Formulas (VI), (VII), and (VIII).
  9. 9 . The optical filter according to claim 7 , wherein the coupling agent composition is a reaction product between 85 to 94 mol % of the silicon compound represented by Formula (V) and 6 to 15 mol % of one or more metal alkoxides selected from Formulas (VI), (VII), and (VIII).
  10. 10 . An optical filter, comprising an absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass; and a resin layer, wherein the resin layer comprises a Si atom and one or more selected from a Ti atom, a Zr atom, and an Al atom, and is provided on the absorbing glass substrate.
  11. 11 . The optical filter according to claim 10 , wherein, in the resin layer, a ratio of a total atomic number of a Ti atom, a Zr atom, and an Al atom to a total number of a Si atom, a Ti atom, a Zr atom, and an Al atom is greater than 0 atomic % and 33.3 atomic % or less.
  12. 12 . The optical filter according to claim 10 , wherein a resin layer comprising hydrolyzed and dehydrated condensates of one or more coupling agents selected from compounds represented by Formulas (I) and (II) below is provided on the absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass: wherein M is a Ti atom, a Zr atom, or an Al atom, R 1 , R 2 and R 3 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms, which comprise or exclude an oxygen atom or a nitrogen atom, and are equal to or different from each other, n is 4 when M is a Ti atom or a Zr atom, or 3 when M is an Al atom, a plurality of —OSiR 1 R 2 R 3 groups are equal to or different from each other, and wherein R 4 , R 5 and R 6 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms, which comprise or exclude an oxygen atom or a nitrogen atom, and are equal to or different from each other, k is a real number between 2 and 15, and a plurality of —OSiR 4 R 5 R 6 groups are equal to or different from each other.
  13. 13 . The optical filter according to claim 10 , wherein a resin layer comprising hydrolyzed and dehydrated condensates of one or more coupling agents selected from compounds represented by Formulas (III) and (IV) below is provided on the absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass: wherein M is a Ti atom, a Zr atom, or an Al atom, R 7 , R 8 and R 9 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, n is 4 when M is a Ti atom or a Zr atom, or 3 when M is an Al atom, and a plurality of —OSi(OR 7 )(OR 8 )(OR 9 ) groups are equal to or different from each other, and wherein R 10 , R 11 and R 12 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, k is a real number between 2 and 15, a plurality of —OSi(OR 10 )(OR 11 )(OR 12 ) groups are equal to or different from each other.
  14. 14 . The optical filter according to claim 13 , wherein the coupling agent represented by Formula (III) is a reaction product between a silicon compound represented by Formula (V) below and one or more selected from metal alkoxides represented by Formulas (VI), (VII), and (VIII) below: wherein R 7 , R 8 and R 9 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 13 , R 14 , R 15 and R 16 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 17 , R 18 , R 19 and R 20 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, and wherein R 21 , R 22 and R 23 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other.
  15. 15 . The optical filter according to claim 10 , wherein the resin layer further comprises a dehydrated condensate of silanol.
  16. 16 . The optical filter according to claim 10 , wherein the resin layer comprising a hydrolyzed and dehydrated condensate of a coupling agent composition that comprises a reaction product between 50 mol % or more and less than 100 mol % of a silicon compound represented by Formula (V) below and greater than 0 mol % and 50 mol % or less of one or more selected from metal alkoxides represented by Formulas (VI), (VII), and (VIII) below is provided on the absorbing glass substrate composed of phosphate-based glass or fluorophosphate-based glass: wherein R 7 , R 8 and R 9 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 13 , R 14 , R 15 and R 16 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, wherein R 14 , R 18 , R 19 and R 20 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other, and wherein R 21 , R 22 and R 23 are straight- or branched-chain hydrocarbon groups having 1 to 10 carbon atoms and are equal to or different from each other.
  17. 17 . The optical filter according to claim 16 , wherein the coupling agent composition is a reaction product between greater than 80 mol % and less than 100 mol % of the silicon compound represented by Formula (V) and greater than 0 mol % and less than 20 mol % of one or more metal alkoxides selected from Formulas (VI), (VII), and (VIII).
  18. 18 . The optical filter according to claim 16 , wherein the coupling agent composition is a reaction product between 85 to 94 mol % of the silicon compound represented by Formula (V) and 6 to 15 mol % of one or more metal alkoxides selected from Formulas (VI), (VII), and (VIII).
  19. 19 . An imaging apparatus, comprising a solid-state image device; an image lens; and the optical filter according to claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATION This is a Continuation of U.S. patent application Ser. No. 16/430,686, filed Jun. 4, 2019, which claims the priority benefit of Japanese Pat. Appl. No. 2018-107112, filed Jun. 4, 2018 and Japanese Pat. Appl. No. 2019-100284, filed May 29, 2019. The disclosure of each of the above-mentioned documents, including the specification, drawings, and claims, is incorporated herein by reference in its entirety. BACKGROUND OF THE DISCLOSURE Field of the Disclosure The present disclosure relates to an optical filter and an imaging apparatus. BACKGROUND OF THE DISCLOSURE Field of the Disclosure In imaging apparatuses adopting a solid-state image device, such as a CCD or CMOS image sensor, mounted in Digital Still Cameras (DSCs) such as a compact digital camera and a digital SLR camera, an InfraRed Cut-off Filter (IRCF) serving to transmit visible light and blocking ultraviolet light and near infrared light to reproduce good colors and clear images has been used (for example, see Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2014-148567)). FIG. 1A and FIG. 1B illustrate schematic views of camera modules as constituents of a DSC. FIG. 1A illustrates a schematic view of a camera module of a compact digital camera mounted in a smartphone, etc., and FIG. 1B illustrates a schematic view of a camera module of a digital SLR camera. With regard to the camera module shown in FIG. 1A, an IRCF 1 selectively reflects ultraviolet light and near infrared light among light transmitted through a lens L so that only light in a visible light region matching the human visibility characteristics is selectively introduced into a module and received by an image sensor IC. Also in the case of the camera module shown in FIG. 1B, an IRCF 1 selectively reflects ultraviolet light and near infrared light among light transmitted through a lens L, and then a cover glass CG serves to prevent penetration of dust while removing α-rays so that only light in a visible light region matching the human visibility characteristics is selectively introduced into a module and accepted into an image sensor IC. The IRCFs have generally been manufactured by providing a reflective film (UVIR film) on an upper surface side (light-incident surface side) of a glass substrate or providing an antireflection film (AR film) on a lower surface side (light-emitting surface side) of a glass substrate. FIG. 2A illustrates schematic views of structures of conventional IRCFs 1. An IRCF 1 shown in FIG. 2A is manufactured by providing a reflective film (UVIR film) 2 on an upper surface side (light-incident surface side) of a glass substrate 3 and providing an antireflection film (AR film) 4 on a lower surface side (light-emitting surface side) of the glass substrate 3 so that the reflective film 2 selectively reflects ultraviolet light and near infrared among light incident from above and only light in a visible light region matching the human visibility characteristics passes through the glass substrate 3 and the AR film 4 and is emitted from the bottom of the AR film 4. However, various components of a digital still camera have been minimized and thinned according to the demand for thinning thereof, thereby being optically designed such that oblique light can be incident on an image sensor. Meanwhile, since the reflection-type IRCF greatly depends upon the wavelength of light, a phase shift wherein a cutoff frequency is shifted to a short wavelength side occurs when the angle of incidence of light increases. Accordingly, in the case of light passing through the center of a lens and light passing through a peripheral portion thereof, angles of incidence of light incident on an IRCF are different from each other, whereby a decrease in color reproducibility may easily occur due to an interference shift. To address such a problem, a reflective film (UVIR film) and an absorbing resin layer are separately provided as IRCFs, or a light-absorbing substrate (absorbing glass substrate) is combined as a glass substrate, thereby reducing a load of a reflective film (UVIR film). In addition, a hybrid-type IRCF capable of exhibiting excellent incidence characteristics while more efficiently reducing ultraviolet light and near infrared light among incident light has been considered. FIG. 2B is a schematic view illustrating an exemplary structure of the hybrid-type IRCF 1. In the case of the IRCF 1 shown in FIG. 2B, a reflective film (UVIR film) 2 is provided on an upper surface side (light-incident surface side) of an absorbing glass substrate 3′ absorbing at least one of ultraviolet light and near infrared light, and an absorbing resin layer 5 and antireflection film (AR film) 4 absorbing ultraviolet light or near infrared light are sequentially provided on a lower surface side (light-emitting surface side) of the absorbing glass substrate 3′. Accordingly, since the reflective film (UVIR film) 2, the absorbing glass substrate