JP-2022514070-A5 -

Dates

Publication Date

20221226

Application Date

20191217

Description

The descriptions of elements in the figures should be understood to apply equally to corresponding elements in other figures unless otherwise indicated. While specific embodiments have been illustrated and described herein, it will be understood by those skilled in the art that various alternative and/or equivalent practices can replace the illustrated and described embodiments without departing from the scope of this disclosure. This application is intended to encompass all adaptable or modified examples of the specific embodiments described herein. Therefore, this disclosure is limited only by the claims and their equivalents. Exemplary embodiments are shown below. [Item 1] An optical system, Reflective polarizer and, A display and a mirror are arranged on the same side of the reflective polarizer and generally facing the reflective polarizer, Equipped with, For normally incident light within a predetermined wavelength range extending over at least a portion of the visible spectrum, The reflective polarizer transmits at least 80% of the incident light having a first polarization state and reflects at least 80% of the incident light having a second polarization state that is orthogonal to it. The mirror reflects at least 80% of the incident light in each of the first and second polarization states, The display is adapted to emit an image for an observer to see, the emitted image includes an emitted central image cone emitted from the center of the display, the emitted central image cone includes emitted central image rays emitted from the center of the display at a central radiation angle greater than about 5 degrees, the reflecting polarizer receives the emitted central image rays at a first incident angle at the center of the reflecting polarizer, and reflects at least 80% of the received emitted central image rays as first reflected image rays, and the mirror is the mirror - The first reflected image ray is received at a second incident angle at the center position of -, at least 80% of the received first reflected image ray is reflected as a second reflected image ray, the reflecting polarizer receives and transmits at least 80% of the second reflected image ray, the center positions of the display, the reflecting polarizer, and the mirror define a central plane including the first, second, and third regions, and with respect to the emitted image ray emitted from the display, propagating along and within the central plane, and before it is incident on the reflecting polarizer for the second time, The first region includes a portion of the emitted image ray that passes through the first region at least once, The second region includes a portion of the emitted image ray that passes through the second region at least twice, The third region includes the portion of the emitted image ray that passes through the third region three times, The first, second, and third regions each have areas A1, A2, and A3, and A3/A2 ≥ 0.2, or 0.22, or 0.24, or 0.26, or 0.28, or 0.3. Optical system. [Item 2] The optical system according to item 1, wherein the first incident angle is approximately 25 to 35 degrees and A3/A2 ≥ 0.3. [Item 3] The optical system according to item 1, wherein the first incident angle is greater than approximately 10 degrees and A3/A2 ≥ 0.3. [Item 4] The optical system according to item 1, wherein the first angle of incidence is approximately 15 to 20 degrees and A3/A2 ≥ 0.4. [Item 5] The optical system according to item 1, wherein the display has a diagonal dimension of less than approximately 5 inches. [Item 6] The optical system according to item 1, wherein the display has a diagonal dimension of less than approximately 4 inches. [Item 7] The optical system according to item 1, wherein the display has a diagonal dimension greater than approximately 1 inch and less than approximately 5 inches. [Item 8] The optical system described in item 1, wherein the first incident angle is greater than approximately 45 degrees and A3/A2 ≥ 0.3. [Item 9] The optical system according to item 1, wherein the visible spectrum extends to at least about 400 nm to about 600 nm. [Item 10] The optical system according to item 1, wherein the display includes a laser light source. [Item 11] The optical system according to item 1, wherein the reflective polarizer includes a linear reference polarizer. [Item 12] The optical system according to item 1, wherein the reflective polarizer includes a circular reference polarizer. [Item 13] The optical system described in item 1, A windshield glass of a vehicle configured to reflect the image transmitted toward the observer by the reflecting polarizer, such that the observer sees a virtual image of the image emitted by the display, Equipped with, Head-up display. [Item 14] The optical system according to item 1, wherein, when the first incident angle is approximately 55 degrees and an image having a spatial frequency of approximately 4 line pairs/mm is emitted from the corner of the