Search

US-12619063-B2 - Lens, ocular optical system, and image display apparatus

US12619063B2US 12619063 B2US12619063 B2US 12619063B2US-12619063-B2

Abstract

A lens including ejector pin marks formed at contacting portions with ejector pins used in molding, with a first side including the ejector pin marks and a second side not including the ejector pin marks. The ejector pin marks are located outside of an optical effective diameter on the first side, and at least one of the ejector pin marks on the first side is located inside an optical effective diameter on the second side.

Inventors

  • Takashi Torii

Assignees

  • CANON KABUSHIKI KAISHA

Dates

Publication Date
20260505
Application Date
20220927
Priority Date
20210929

Claims (16)

  1. 1 . A lens molded from a resin, the lens comprising: a first side; and a second side opposite to the first side; the first side including: a first side optical effective diameter; an inclined surface; a flange portion; and ejector pin marks formed at contacting portions with ejector pins used in molding, the inclined surface being disposed radially outside the first side optical effective diameter and radially inside the flange portion; the second side including a second side optical effective diameter that is larger than the first side optical effective diameter; wherein the ejector pin marks are provided on the inclined surface; wherein the ejector pin marks are located outside the first side optical effective diameter, and wherein at least one of the ejector pin marks is located inside the second side optical effective diameter.
  2. 2 . The lens according to claim 1 , wherein the ejector pin marks have surface roughness substantially equal to surface roughness of the inclined surface.
  3. 3 . The lens according to claim 1 , wherein the ejector pin marks are painted in black.
  4. 4 . The lens according to claim 1 , wherein the lens has an outer diameter of φ50 mm or less.
  5. 5 . An ocular optical system configured to guide light from a display element to an exit pupil, the ocular optical system comprising: the lens according to claim 1 ; a first phase plate disposed between the display element and the lens; a semi-transmission reflective surface disposed on a surface of the lens on a side opposite to a side provided with the first phase plate; a second phase plate disposed on a side of the lens opposite to the side provided with the first phase plate; and a polarizing beam splitting element disposed on a side of the second phase plate opposite to a side provided with the lens.
  6. 6 . The ocular optical system according to claim 5 , wherein the polarizing beam splitting element reflects incident first linearly polarized light and allows second linearly polarized light in a polarization direction substantially orthogonal to a polarization direction of the first linearly polarized light to pass therethrough.
  7. 7 . The ocular optical system according to claim 5 , wherein the ejector pin marks provided on the lens are arranged between the display element and the semi-transmission reflective surface.
  8. 8 . An image display apparatus, comprising: the ocular optical system according to claim 5 ; and the display element.
  9. 9 . The image display apparatus according to claim 8 , wherein the display element radiates unpolarized light, and wherein the ocular optical system further includes a polarizing plate that is disposed between the display element and the first phase plate.
  10. 10 . The lens according to claim 1 , wherein the inclined surface contributes to maintenance of a substantially equal thickness of the lens.
  11. 11 . The lens according to claim 1 , wherein the inclined surface continuously connects a peripheral edge of the first side optical effective diameter with the flange portion.
  12. 12 . The lens according to claim 1 , wherein the inclined surface is a polished surface.
  13. 13 . The lens according to claim 3 , wherein a region painted in black includes the inclined surface.
  14. 14 . The lens according to claim 3 , wherein regions painted in black include areas other than the first side optical effective diameter.
  15. 15 . The ocular optical system according to claim 5 , wherein the lens is the largest member of the ocular optical system.
  16. 16 . The ocular optical system according to claim 5 , wherein the first side of the lens faces the display element and the second side of the lens faces the semi-transmission reflective surface.

Description

BACKGROUND Field of the Disclosure The present disclosure relates to a lens, an ocular optical system using the lens, and an image display apparatus such as a head-mounted display (HMD) that enables observation of an image on a display element in an enlarged manner through the ocular optical system. Description of the Related Art In recent years, a wide angle of view of an ocular optical system has been demanded in a field of the HMD. Further, the HMD is also demanded to be lightweight, to secure a nose relief portion, to deal with various interpupillary distances, and to be downsized at the same time because the HMD is mounted on a head in observing an image. Thus, the wide angle of view is desirably provided not by a simple increase in size of the ocular optical system, but by a reduction of a ratio of a non-optical effective diameter in the ocular optical system. Japanese Patent No. 5361173 discusses a technique for fabricating a lens having high surface accuracy in an area of an optical effective diameter, and ejector pins used in molding of the lens are installed in a flange portion that is an area of a non-optical effective diameter. Further, in Japanese Patent No. 5361173, the ejector pins are installed outside an optical effective diameter on a second surface of the lens. Typically, the lens molded with the ejector pins installed is high in moldability. In Japanese Patent No. 5361173, however, the lens may be increased in size due to the flange portion in which installation of the ejector pins is taken into consideration. Japanese Patent Application Laid-Open No. 2020-85956 discusses a configuration of an ocular optical system using polarization. In Japanese Patent Application Laid-Open No. 2020-85956, the above-described non-optical effective diameter and the above-described ejector pins are not discussed; however, if a flange portion in which installation of the ejector pins is taken into consideration is provided outside an optical effective diameter on a second surface of a lens, the ocular optical system may be increased in size due to the flange portion. SUMMARY According to an aspect of the present disclosure, a lens is provided including ejector pin marks formed at contacting portions with ejector pins used in molding. The lens comprises a first side including the ejector pin marks, wherein the ejector pin marks are located outside of a first side optical effective diameter, and a second side not including the ejector pin marks, wherein at least one of the ejector pin marks on the first side is located inside a second side optical effective diameter. Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating an example of appearance of an image display apparatus according to an exemplary embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of an internal configuration in cross section taken along line A-A of the image display apparatus illustrated in FIG. 1. FIG. 3 is a projection diagram schematically illustrating an example of a configuration of a lens illustrated in FIG. 2. FIG. 4 is a projection diagram schematically illustrating an example of the configuration of the lens illustrated in FIG. 2. FIG. 5 is a projection diagram schematically illustrating an example of the configuration of the lens illustrated in FIG. 2. FIG. 6 is a projection diagram schematically illustrating an example of the configuration of the lens illustrated in FIG. 2. DESCRIPTION OF THE EMBODIMENTS An exemplary embodiment of the present disclosure is described below with reference to drawings. FIG. 1 is a diagram illustrating an example of appearance of an image display apparatus 10 according to the exemplary embodiment of the present disclosure. A user (not illustrated) can observe an image by wearing the image display apparatus 10 on the user's head. As the image display apparatus 10, for example, the above-described head-mounted display (HMD) can be adopted. FIG. 2 is a diagram illustrating an example of an internal configuration in a cross-section taken along line A-A of the image display apparatus 10 illustrated in FIG. 1. As illustrated in FIG. 2, the image display apparatus 10 includes an ocular optical system 100 and a display element 200. The ocular optical system 100 is an optical system that guides light from the display element 200 to an exit pupil. More specifically, the ocular optical system 100 is an optical system that enlarges and projects an original image displayed on the display element 200 as a virtual image and guides the original image to an eye E of the user. The ocular optical system 100 includes a polarizing plate 110, a first phase plate 120, a lens 130, a half mirror 140 constituting a semi-transmission reflective surface, a lens 150, a second phase plate 160, a polarizing beam splitter (PBS)