US-20260126652-A1 - VIRTUAL IMAGE DISPLAY APPARATUS AND OPTICAL UNIT

US20260126652A1US 20260126652 A1US20260126652 A1US 20260126652A1US-20260126652-A1

Abstract

A virtual image display apparatus includes a lens barrel having a first opening through which image light passes; a first lens fixed inside the lens barrel; a sealing member fixed to the first opening and configured to seal the first opening; and an image display panel fixed outside the lens barrel and configured to generate the image light to be output toward the first lens via the sealing member. The sealing member includes a polarization control member configured to convert the image light into predetermined polarized light.

Inventors

Tokito YAMAGUCHI

Assignees

SEIKO EPSON CORPORATION

Dates

Publication Date: 20260507
Application Date: 20251001
Priority Date: 20241002

Claims (13)

1 . A virtual image display apparatus, comprising: a lens barrel having a first opening through which image light passes; a first lens fixed inside the lens barrel; a sealing member fixed to the first opening and configured to seal the first opening; and an image display panel fixed outside the lens barrel and configured to generate the image light to be output toward the first lens via the sealing member, wherein the sealing member includes a polarization control member configured to convert the image light into predetermined polarized light.
2 . The virtual image display apparatus according to claim 1 , wherein the sealing member has a circumferential edge portion fixed to the first opening, and a central portion where the polarization control member is disposed and through which the image light passes.
3 . The virtual image display apparatus according to claim 1 , wherein the sealing member further includes a support plate configured to support the polarization control member, and the first opening is provided with a first holder configured to hold an end portion of the support plate.
4 . The virtual image display apparatus according to claim 3 , further comprising a dustproof member configured to fix the sealing member to the lens barrel while reliably preventing dust from entering the first opening of the lens barrel.
5 . The virtual image display apparatus according to claim 4 , wherein the dustproof member includes a tape having elasticity and configured to temporarily fix the sealing member to the first opening of the lens barrel while reliably preventing dust from entering the first opening of the lens barrel, and a first adhesive having fluidity that allows, before cured, adjustment of a position and a direction of the polarization control member with respect to the lens barrel and fixes, after cured, the position and the direction of the polarization control member with respect to the lens barrel.
6 . The virtual image display apparatus according to claim 1 , further comprising a support frame configured to support the image display panel, wherein the lens barrel further includes a second holder configured to hold the support frame, and the virtual image display apparatus further comprises a second adhesive that is curable at any timing and fixes the support frame to the second holder of the lens barrel in a state in which a position and a direction of the image display panel with respect to the lens barrel are adjusted.
7 . The virtual image display apparatus according to claim 1 , wherein the lens barrel further includes a second opening through which the image light passing through the first lens exits, and the first lens is configured to seal the second opening.
8 . The virtual image display apparatus according to claim 7 , wherein the polarization control member is configured to convert the image light from the image display panel into circularly polarized light, a half-silvered mirror is provided at a first optical surface of the first lens that is a surface facing the first opening, a polarization conversion member configured to convert linearly polarized light into circularly polarized light and convert circularly polarized light into linearly polarized light is provided at a second optical surface of the first lens that is a surface facing the second opening, and a polarization optical element configured to reflect first linearly polarized light and transmit second linearly polarized light is provided on an outer side of the polarization conversion member at the second optical surface.
9 . The virtual image display apparatus according to claim 8 , wherein the first lens includes a pancake lens having a convex surface as the first optical surface and a concave surface as the second optical surface.
10 . The virtual image display apparatus according to claim 8 , wherein the first lens includes a plano-convex lens having a convex surface as the first optical surface and a planar surface as the second optical surface, and the virtual image display apparatus further comprises a second lens as a plano-concave lens having a concave surface as a third optical surface facing the first optical surface, and a planar surface as a fourth optical surface facing the first opening.
11 . The virtual image display apparatus according to claim 1 , wherein the image display panel includes an organic light emitting diode (OLED) panel configured to generate the image light, and the polarization control member includes a circularly polarizing element configured to convert the image light from the image display panel into circularly polarized light.
12 . The virtual image display apparatus according to claim 1 , wherein the image display panel includes a liquid crystal panel configured to generate the image light, and the polarization control member includes a polarizing plate configured to extract a predetermined linearly polarized component of the image light from the image display panel as linearly polarized light, and a quarter waveplate configured to convert the linearly polarized light into circularly polarized light.
13 . An optical unit, comprising: a lens barrel having a first opening through which image light passes; a first lens fixed inside the lens barrel; a sealing member fixed to the first opening and configured to seal the first opening; and an image display panel fixed outside the lens barrel and configured to generate the image light to be output toward the first lens via the sealing member, wherein the sealing member includes a polarization control member configured to convert the image light into predetermined polarized light.

Description

The present application is based on, and claims priority from JP Application Serial Number 2024-173044, filed Oct. 2, 2024, the disclosure of which is hereby incorporated by reference herein in its entirety. BACKGROUND 1. Technical Field The present disclosure relates to a virtual image display apparatus and an optical unit that allow observation of a virtual image, and particularly relates to a virtual image display apparatus and an optical unit using a lens barrel that incorporates a lens and is sealed from the outside. 2. Related Art There is a known system including: a central mount; a rotating collar coupled to the central mount and configured to rotate around the central mount; and two or more holding prongs attached to the rotating collar, the holding prongs configured to hold a first lens while the rotating collar rotates the first lens around the optical axis of a pancake lens display assembly including a second lens arranged optically in series with respect to the first lens, the rotating collar configured to rotate the first lens to position a first orientation axis of a quarter waveplate on the first lens in such a way that the first orientation axis inclines by a certain angle with respect to a second orientation axis of a reflective polarizer on the second lens; an illumination source configured to emit test light via the first lens and the second lens; and a sensor configured to receive the test light emitted by the illumination source, the certain angle being an angle at which the light having passed through the second lens and then the first lens is substantially circularly polarized (JP-T-2022-501630). JP-T-2022-501630 is an example of the related art. The system described above has a structure in which the panel-side lens surface of the first lens is sealed together with the panel by a lens barrel part. In the structure described above, since a pancake lens portion is not sealed, foreign matter leaking from the interior of the pancake lens or the portion that seals the panel and the lens barrel is likely to adhere to the panel-side lens surface or the panel surface, and the adhesion leads to deterioration of image quality. To improve the quality of an image displayed by a head mounted display (HMD) at the time of the assembly of the panel, even when the angle of rotation of a polarizing element bonded to the panel surface needs to be adjusted in accordance with the direction in which the pancake lens rotates, or the positions in the optical axis direction, the horizontal direction, and the rotation direction need to be adjusted for adjustment of the focusing of a displayed image, there is a risk of interference with the lens barrel part, so that the range of each of the various adjustments is restricted. The panel position adjustment is therefore unlikely to be sufficiently performed, so that the assembly may not be performed with the image quality sufficiently ensured. SUMMARY A virtual image display apparatus according to an aspect of the present disclosure includes a lens barrel having a first opening through which image light passes; a first lens fixed inside the lens barrel; a sealing member fixed to the first opening and configured to seal the first opening; and an image display panel fixed outside the lens barrel and configured to generate the image light to be output toward the first lens via the sealing member, and the sealing member includes a polarization control member configured to convert the image light into predetermined polarized light. An optical unit according to another aspect of the present disclosure includes a lens barrel having a first opening through which image light passes; a first lens fixed inside the lens barrel; a sealing member fixed to the first opening and configured to seal the first opening; and an image display panel fixed outside the lens barrel and configured to generate the image light to be output toward the first lens via the sealing member, and the sealing member includes a polarization control member configured to convert the image light into predetermined polarized light. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exterior front view illustrating a state in which virtual image display apparatuses according to a first embodiment are mounted. FIG. 2 is a side cross-sectional view illustrating the internal structure of a display optical system. FIG. 3 is a partial cross-sectional view illustrating detailed structures of portions of the display optical system. FIG. 4 is a conceptual view illustrating the optical operation of the virtual image display apparatus according to the first embodiment. FIG. 5 is a perspective cross-sectional view illustrating the structure of a lens barrel in the first embodiment. FIG. 6 is a perspective cross-sectional view illustrating the structure of the lens barrel in the first embodiment. FIG. 7 is a partial cross-sectional view illustrating the structure of the lens barrel in the first embodiment. FIG. 8 is a co