CPC B29C 64/286 (2017.08) [B33Y 30/00 (2014.12); F21V 5/04 (2013.01); F21V 7/04 (2013.01); F21V 13/04 (2013.01)] | 10 Claims |
1. An illumination module, comprising:
a light emitting unit;
an optical lens with positive refractive power, wherein at least one of an object-side surface and an image-side surface of the optical lens is an asymmetrical surface, and the light emitting unit is provided at an object side of the optical lens; and
a concave mirror provided at an image side of the optical lens, wherein the concave mirror acts as an optical path folding element, and
light emitted by the light emitting unit passes through the optical lens and is reflected by the concave mirror to be a parallel light ray;
wherein a focal length of the concave mirror is from 60 mm to 100 mm, and an air gap in a paraxial region between the image-side surface of the optical lens and a mirror surface of the concave mirror is from 150 mm to 250 mm.
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