Optical branching device with internal waveguide

An optical waveguide device comprising a region formed in a transparent substrate, the region having a refractive index higher than a refractive index of the transparent substrate and defining an optical waveguide within the transparent substrate, said optical waveguide having first and second optical waveguide elements, each of the waveguide elements having one end connected to the one end of the other optical waveguide element in a substantially V-shape in the vicinity of a first surface of said transparent substrate, a connecting portion of the connected ends of the two optical waveguide elements being exposed to the first surface of said transparent substrate;

• and
• wherein an axis of each of said optical waveguide elements lies within an imaginary plane perpendicular to the first surface of said transparent substrate and is inclined at the same angle with respect to a line normal to the first surface of said transparent substrate, and the axes of the first and second optical waveguide elements also intersecting one another at the surface of the transparent substrate where the connecting portion is exposed;
• wherein an optical filter is arranged on each surface portion of said transparent substrate where the connecting portion is exposed;
• and
• wherein the optical filter transmits light of predetermined wavelengths and reflects light of other wavelengths, respectively.

An optical waveguide device comprising a region formed in a transparent substrate and having a refractive index higher than a refractive index of the transparent substrate for defining an optical waveguide within the transparent substrate, said optical waveguide having first and second optical waveguide elements, each element having one end connected to the one end of the other element in a substantially V-shape in the vicinity of a first surface of said transparent substrate, a connecting portion of the connected ends of said first and second optical waveguide elements being exposed to the first surface of said transparent substrate, and a remaining end of each of the first and second optical waveguide elements being exposed to a surface of the transparent substrate other than said first surface;

• and
• a second transparent substrate including a region within the second transparent substrate having a refractive index higher than the refractive index of said second transparent substrate defining a second continuous, monolithic optical waveguide in the second transparent substrate, said second optical waveguide having first and second optical waveguide elements, each element having one end connected to one end of the other optical waveguide element in a substantially V-shape in the vicinity of a first surface of said second transparent substrate, a connecting portion of the connected ends of the first and second optical waveguide elements of the second transparent substrate being exposed to the first surface of said second transparent substrate, and a remaining end of each of said first and second optical waveguide elements of the second transparent substrate being exposed to a surface of the second transparent substrate other than said first surface of said second transparent substrate, the two transparent substrates being positioned with the first surfaces of each transparent substrate and with the connecting portions exposed to the first surfaces of each transparent substrate in opposition;
• and
• a liquid crystal between the first surfaces and the connecting portions of the two transparent substrates in opposition.

An optical waveguide device comprising a region formed in a transparent substrate and having a refractive index higher than a refractive index of the transparent substrate for defining an optical waveguide within the transparent substrate, said optical waveguide having first and second optical waveguide elements, each element having one end connected to the one end of the other element in a substantially V-shape in the vicinity of a first surface of said transparent substrate, a connecting portion of the connected ends of said first and second optical waveguide substrate, and a remaining end of each of the first and second optical waveguide elements being exposed to a surface of the transparent substrate other than said first surface;

• and
• a third optical waveguide element within the transparent substrate formed to branch from said second optical waveguide element at a midpoint between the two ends of said second optical waveguide element forming an acute angle towards the connecting portion with respect to said second optical waveguide element;
• a portion of light transmitted through said first optical waveguide element passing through an optical filter arranged at a portion of the first surface of said transparent substrate where said connecting portion is exposed, a remaining portion of light being reflected by said optical filter through the second waveguide element;
• and
• light input through said third optical waveguide element merging with said remaining portion of light transmitted through said second optical waveguide element.