Magnetic field measuring apparatus and manufacturing method of magnetic field measuring apparatus

• US 10,036,786 B2
• Filed: 06/06/2017
• Issued: 07/31/2018
• Est. Priority Date: 06/14/2016
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Ueno, Hitoshi
• Primary Examiner(s): Lee, Seung
• Application Number:
  US15/614,961
• Publication Number:
  US 20170356969A1
• Time in Patent Office: 420 Days
• CPC Class Codes: G01R 33/032 using magneto-optic devices, e.g. Faraday or Cotton-Mouton effect
• CPC Class Codes: G01R 33/243 Spatial mapping of the polarizing magnetic field
• CPC Class Codes: G01R 33/26 using optical pumping

Abstract

A magnetic field measuring apparatus includes a first cell and a second cell in which alkali metal atoms are respectively enclosed, a light guide that enters laser light into the first cell and the second cell, and a position adjustment mechanism, and a position of a second reference surface with respect to a first reference surface is adjusted and orientations of optical axes of a beam light relating to the first reference surface and a beam light relating to the second reference surface are the same direction.

Claims

1. A magnetic field measuring apparatus comprising:

a light irradiation part that radiates linearly-polarized light;

a first cell and a second cell with alkali metal atoms enclosed therein sequentially placed in a sensitive direction of a magnetic field;

a first optical device placed on a first reference surface and entering the linearly-polarized light into the first cell; and

a second optical device placed on a second reference surface and entering the linearly-polarized light into the second cell,

wherein a position of the second reference surface with respect to the first reference surface is adjusted so that an orientation of an optical axis of a first reflected light of light relating to the first reference surface and an orientation of an optical axis of a second reflected light of light relating to the second reference surface in parallel to that light may be the same direction.

2. The magnetic field measuring apparatus according to claim. 1, further comprising an optical axis detection part that can radiate beam light as the light and detect an orientation of an optical axis of the first reflected light of the beam light relating to the first reference surface and an orientation of an optical axis of the second reflected light of the beam light relating to the second reference surface.

3. The magnetic field measuring apparatus according to claim 1, reflection members are provided on the first reference surface and the second reference surface.

4. The magnetic field measuring apparatus according to claim 1, further comprising:

a third cell placed in a direction orthogonal to the sensitive direction with respect to the first cell; and

a fourth cell placed in a direction orthogonal to the sensitive direction with respect to the second cell.

5. The magnetic field measuring apparatus according to claim 4, wherein the light irradiation part includes a first light irradiation part that irradiates the first cell and the third cell with the linearly-polarized light and a second light irradiation part that irradiates the second cell and the fourth cell with the linearly-polarized light.

6. The magnetic field measuring apparatus according to claim 1, wherein the sensitive direction of the magnetic field and incident directions of the linearly-polarized light in the first cell and the second cell cross.

7. A manufacturing method of a magnetic field measuring apparatus including

a light irradiation part that radiates linearly-polarized light,

a first cell and a second cell with alkali metal atoms enclosed therein,

a first optical device placed on a first reference surface and entering the linearly-polarized light into the first cell, and

a second optical device placed on a second reference surface and entering the linearly-polarized light into the second cell,

the method comprising:

a placement step of sequentially placing the first cell and the second cell in a sensitive direction of a magnetic field;

an optical axis detection step of detecting an orientation of an optical axis of a first reflected light of light relating to the first reference surface and an orientation of an optical axis of a second reflected light of light relating to the second reference surface in parallel to that light; and

a position adjustment step of adjusting a position of the second reference surface with respect to the first reference surface so that the orientation of the optical axis of the first reflected light and the orientation of the optical axis of the second reflected light may be the same direction based on a result of the optical axis detection step.

8. The manufacturing method according to claim 7, wherein the optical axis detection step includes:

a first step of detecting the orientation of the optical axis of the first reflected light; and

a second step of detecting the orientation of the optical axis of the second reflected light, and

the second step is performed after the placement step and detects the orientation of the optical axis of the second reflected light with reference to the orientation of the optical axis of the first reflected light detected at the first step.