Display Device with an Optical Combiner Corrected for Chromatic Aberrations

Abstract

A head-up display or helmet-mounted display device includes at least one image source configured to emit a first image in at least two different spectral bands. A relay optics includes at least one first optical element for reflecting the two spectral bands and a semi-reflecting second optical element. The relay optics and the semi-reflecting second optical element are arranged so as to give, from the first image emitted by the image source, a second image at infinity. In the device, when the image source is a dichromatic source, the reflecting first optical element comprises a thin plate, the first side of which comprises a first treatment reflecting the first spectral band and transmitting the second spectral band, and the second side of which comprises a second treatment reflecting at least the second spectral band, the thickness of said plate being such that the axial chromatic aberration, generated by the other optical elements composing the relay optics, existing between the two spectral bands, is substantially cancelled.

Dependencies are inferred from the claim text.