JPS62247209A - Optical gyroscope - Google Patents

Abstract

PURPOSE:To obtain a flat and thin-type optical gyroscope, by forming a waveguide path in a spiral shape on a waveguide substrate and permitting it to be serviceable as an optical loop sensor. CONSTITUTION:A waveguide path 2 of 5-10mum thick is shaped in a spiral shape on a circular-disc waveguide path substrate established on a single waveguide path substrate 1 by installing laser-diode-originated light source 3, polarizing member 4, detector 5, light-branching members 6a, 6b and optical fiber 8 for bypass. The waveguide path 2 is so formed that, a film is formed on a silicon substrate using SiO2, TiO2 and reactive ion-etching is conducted and the etched surface is covered with SiO2 as a clad surface. A beam of light from the source 3 is transmitted to the spiral-shape waveguide path 2 via light- branching member 6a, polarizing member 4, light-branching member 6b and directed from the other end of the waveguide path 2 to the light-branching members 6b, 6b by the optical fiber 8 for bypass and reaches the detector 5.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an optical gyroscope, in which a part corresponding to the bobbin of a conventional optical fiber gyro is formed into a spiral leading waveguide like the grooves of a record. This is what I did.

(Prior Art) A conventional fiber optic gyro has a configuration as shown in FIG. In this optical fiber gyro, an optical loop sensor A is formed by winding an optical fiber around a fiber bobbin.

The Konohikari fiber gyro allows light to enter an optical fiber wound around a bobbin in both left and right directions, and detects the frequency change and phase change of the inner light to determine the rotational angular velocity.

(Considerations of the Prior Art) Conventional optical fiber gyros have to connect the optical fiber to the optical branching section and the phase modulator section, so it is difficult to make them smaller or thinner.

In order to miniaturize this optical fiber gyro, the size of the fiber bobbin can be made smaller, but the allowable bending diameter of the fiber is limited by the thickness of the fiber.
・Fi per turn/(l) As the length becomes shorter, the length must be determined by the number of windings, so there is a limit to how small the bobbin can be made. Also, as the number of windings increases, the winding becomes more difficult due to tension and fiber. / Uniform winding (
There is also the problem that it is difficult to carry out step 1.

(R1 aspect of the invention) An object of the present invention is to provide an optical gyroscope having an eleven plate shape and a sock type.

(Steps for Solving Problems) The optical gyroscope of the present invention is an optical loop sensor in which a waveguide 2 is spirally formed on a waveguide 1 (plate 1).

(Embodiment of the invention): The fS1 diagram is an embodiment of the optical gyroscope of the invention.

Reference numeral 1 in FIG. 1 is a disk-shaped waveguide substrate, on which a waveguide 2 of 5 to 10 μm is spirally formed like the grooves on a record plate.

In Figure 1, 3 is a laser diode light source, and 4 is polarized light Y.
5 is a detector, 6a and 6b are optical branching sections, 7 is a phase modulation section, and 8 is a bypass optical fiber. Although these are provided on one waveguide substrate 1 for high printing, they may be provided externally separately from the waveguide board 1.

The bypass optical fiber 8 can be constructed by stacking the leading waveguides and connecting them from front to back like a through hole in an electric circuit, or by making another waveguide 1 (another plate 1 and connecting it to the optical branch). Make it by doing something like this.

Currently, the Nori wave path 2 is made of 5i02 and Ti on the silicon substrate 1-.
A film using O2 is made and then subjected to reactive ion etching, and 5102 is attached to the ball using the CVD method to form a cladding. However, in the future, this waveguide 2 will also be In
By changing to a substrate made of P or GaAs,
It is now possible to create a light source at the same time, and optical gyro - optical I
It becomes C gyro().

(Operation of the invention) The light from the light source 3 in FIG.
, is transmitted to the spiral waveguide 2 through the optical branching part 6b,
The light is guided from the other end of the waveguide 2 to optical branching parts 6b, 6b by a bypass optical fiber 8, and reaches the detector 5.

(Effects of Effect II) The optical scope of the present invention has the following effects.

(1) Since the optical loop sensor is made into a mosaic surface, it becomes smaller and smaller.
Can be made thinner. If the total thickness is just the main body part, it is approximately 5m.
It becomes thinner to m.

(2) Integration with other optical components becomes an advantage.

(3) Since the waveguide 2 can be made longer by narrowing the helical interval of the waveguide 2, even if the waveguide 2 is made longer, it does not become larger.

(4) It is easy to shield to prevent the influence of Jlt ball magnetism.

[Brief explanation of drawings]

Figure 1 shows an example of an unreleased IJI f-plate type optical gyro.
The top view and FIG. 2 are explanatory diagrams of a conventional optical gyro. 1 is the waveguide substrate 2 is the waveguide applicant. electric “jl”

Claims (3)

[Claims] (1) An optical gyroscope characterized in that an optical loop sensor is formed by forming a waveguide in a spiral shape on a waveguide substrate. (2) The optical gyroscope according to claim 1, wherein the optical loop sensor is created at the same time as the optical branching section, the optical modulating section, etc., and is hybridized with an external light source and a detector. (3) The optical gyroscope according to claim 1, in which a waveguide, a light source, and a detector are integrally manufactured on a semiconductor substrate using G_dA_s or I_nP.