JP2015102613A5

JP2015102613A5 -

Info

Publication number: JP2015102613A5
Application number: JP2013241618A
Authority: JP
Filing date: 2013-11-22
Publication date: 2016-12-22

Claims

A light guide provided with a light emitting portion;
By the light guide body diffracts at least a part of the light guided, a diffractive optical element and the light guide from the light emitting portion of the light guide body to take out at least part of the light guided,
A wavelength selection unit that selects and transmits light of a predetermined wavelength;
Have
The light guided by the light guide is
Light of a first wavelength;
Light of a second wavelength different from the first wavelength;
Including
The diffractive optical element is
A first diffraction region having a diffraction characteristic in which the diffraction efficiency of the light of the first wavelength is higher than the diffraction efficiency of the light of the second wavelength;
A second diffraction region having a diffraction characteristic in which the diffraction efficiency of the light of the second wavelength is higher than the diffraction efficiency of the light of the first wavelength;
With
The wavelength selector is
In a plan view seen from a direction perpendicular to the light emitting part of the light guide,
A first wavelength selection region that is provided at a position overlapping the first diffraction region and selectively transmits light of the first wavelength;
A second wavelength selection region that is provided at a position overlapping the second diffraction region and selectively transmits the light of the second wavelength;
Comprising
An optical device characterized by that.

The optical device according to claim 1.
The light guide is
A light incident portion for allowing light to be incident on the light guide by geometric optical means;
An optical device characterized by that.

The optical device according to claim 1 or 2,
Comprising one light guide,
The light guided by the one light guide is
Including light of a third wavelength different from the first wavelength and the second wavelength;
The diffractive optical element is
A third diffraction region having a diffraction efficiency higher than the diffraction efficiency of the light of the first wavelength and the diffraction efficiency of the light of the second wavelength;
The wavelength selector is
In a plan view seen from a direction perpendicular to the light emitting part of the light guide,
A third wavelength selection region that is provided at a position overlapping the third diffraction region and that selectively transmits light of the third wavelength;
An optical device characterized by that.

The optical device according to any one of claims 1 to 3,
The diffractive optical element is
A light transmissive diffractive optical element,
An optical device characterized by that.

The optical device according to any one of claims 1 to 4,
The diffractive optical element is
A surface relief type diffractive optical element provided with a concavo-convex structure on one surface,
An optical device characterized by that.

The optical device according to claim 5.
The height of the convex portion of the concave-convex structure is
Provided to be equal over the entire diffractive optical element,
An optical device characterized by that.

The optical device according to claim 5.
The height of the convex part of the concavo-convex structure provided in the first diffraction region is
Determined based on the first wavelength;
The height of the convex portion of the concavo-convex structure provided in the second diffraction region is
Determined based on the second wavelength;
An optical device characterized by that.

The optical device according to any one of claims 5 to 7,
The direction in which the convex portion of the concavo-convex structure provided in the first diffraction region extends is as follows:
Provided in the same direction as the direction in which the convex part of the concavo-convex structure provided in the second diffraction region extends,
An optical device characterized by that.

The optical device according to any one of claims 1 to 8,
The wavelength selector is
Provided between the diffractive optical element and the light emitting portion of the light guide;
An optical device characterized by that.

The optical device according to any one of claims 1 to 8,
The diffractive optical element is
Provided on the surface of the light guide,
The wavelength selector is
Provided on the opposite side of the light emitting part of the light guide across the diffractive optical element,
An optical device characterized by that.

The optical device according to any one of claims 1 to 10,
The wavelength selector is
It is a color filter of wavelength selective absorption type or wavelength selective reflection type,
An optical device characterized by that.

The optical device according to claim 3.
The pitch of the plurality of diffraction regions including the first diffraction region, the second diffraction region, and the third diffraction region is:
The pupil diameter of the exit-side optical system that controls the optical path of the light extracted from the light guide by the diffractive optical element is less than or equal to the length divided by the number of types of wavelengths of light guided by the light guide. is there,
An optical device characterized by that.

The optical device according to any one of claims 1 to 12,
An image forming unit that emits image light;
Comprising
A display device characterized by that.