Optical element, head-up display and light source unit

摘要

An optical element includes a first microlens array unit and a second microlens array unit in each of which a plurality of microlenses are arranged. The first and second microlens array units are arranged opposite to each other with a distance which is longer than a focal length of the microlenses arranged in the first microlens array unit. The first microlens unit is arranged on a light-incident side with respect to the second microlens array unit. The interval between the microlenses arranged in the second microlens array unit is narrower than the interval between the microlenses arranged in the first microlens array unit. The optical element can appropriately suppress the occurrence of excessive pixel bright spot.

主权项

1. A light source unit comprising:
a light source; and an optical element comprising a first microlens array unit and a second microlens array unit in each of which plural microlenses are arranged, wherein the first microlens array unit and the second microlens array unit are arranged opposite to each other with a distance longer than a focal length of the microlenses arranged in the first microlens array unit, wherein an interval of the microlenses arranged in the second microlens array unit is narrower than an interval of the microlenses arranged in the first microlens array unit, wherein the first microlens array unit is arranged on a light-incident side of a light emitted by the light source with respect to the second microlens array unit, wherein the first microlens array unit and the second microlens array unit are arranged such that the light emitted by the first microlens array unit is directly incident on the second microlens array unit, wherein the intervals between the microlenses arranged in the first microlens array unit and the second microlens array unit are set such that the light focused by one microlens in the first microlens array unit is incident on and divided by two or more microlenses in the second microlens array unit, and wherein the light focused by two neighboring ones of the microlenses in the first microlens array unit is incident upon a same one of the microlenses in the second microlens array unit.