Head Up Display

Abstract: An HUD (1) according to the present invention includes: a light source (2) that projects an image; a projection image display member (3) on which the image is projected; and a polarization control layer (4). The polarization control layer (4) is disposed between the light source (2) and the projection image display member (3) and has a function of changing the polarization state of light emitted from the light source (2). A polarization component that becomes S-polarized light with respect to an incident surface of the projection image display member (3) and a polarization component that becomes P-polarized light with respect to the incident surface satisfy [expression 1] and [expression 2], and in the projection image display member (3), the average reflectance at wavelengths of 400-700 nm when linearly polarized light of P-polarized light is incident at an incident angle of 60° thereon is 5-100%, and the transmittance of visible light when natural light is incident at an incident angle of 0° thereon is 50-100%. [Expression 1]: Sratio2 < Sratio1 [Expression 2]: Pratio2 = 0.51 Herein, Sratio1 is the ratio of the S-polarization component in the light emitted from the light source (2), Sratio2 is the ratio of the S-polarization component in the light incident on the projection image display member (3), and Pratio2 is the ratio of the P-polarization component in the light incident on the projection image display member (3).

Patent Information

Applicants

Inventors

Specification

Documents

Application Documents