ATOMIC OSCILLATOR AND ELECTRONIC DEVICE

• US 20190109597A1
• Filed: 11/28/2018
• Published: 04/11/2019
• Est. Priority Date: 10/19/2016
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: MATSUDA, Kenji
• Granted Patent: US 10,756,743 B2
• Time in Patent Office: Days
• CPC Class Codes: G04F 5/145 using Coherent Population Trapping
• CPC Class Codes: H01S 1/06 Gaseous , i.e. beam masers
• CPC Class Codes: H03B 17/00 Generation of oscillations using radiation source and detector, e.g. with interposed variable obturator
• CPC Class Codes: H03L 7/26 using energy levels of molecules, atoms, or subatomic particles as a frequency reference

Abstract

An atomic oscillator includes a light source, a gas cell including an internal space in which an alkali metal atom is sealed, and a photodetector to detect light emitted from the light source and passing through the gas cell. A radiation region of the light source is wider than a sectional area of the internal space at a distal end of the gas cell relative to the light source.

Claims

1. An atomic oscillator, comprising:

a light source;

a gas cell including an internal space in which an alkali metal atom is sealed; and

a light detecting portion to detect light emitted from the light source and passing through the gas cell;

wherein

a radiation region of the light source is wider than a sectional area of the internal space at a distal end of the gas cell relative to the light source.

2. The atomic oscillator according to claim 1, wherein a width of the radiation region of the light source increases in the internal space toward the light detecting portion.

3. The atomic oscillator according to claim 1, wherein the gas cell comprises:

an entrance window at which the light from the light source enters the gas cell, the entrance window being provided at a proximal end of the gas cell relative to the light source;

an exit window at which the light passing through the internal space exits the gas cell toward the light detecting portion, the exit window being provided at the distal end of the gas cell; and

a lateral wall that defines the entrance window and the exit window; and

the lateral wall includes a light blocking portion defined by a light absorbing member.

4. The atomic oscillator according to claim 3, wherein the light blocking portion has a light absorption coefficient of about 23 cm⁻

1 or more.

5. The atomic oscillator according to claim 1, further comprising:

a light blocking member to block a portion of the light emitted from the light source so that the portion of the light does not enter the gas cell;

wherein

the light blocking member is provided between the light source and the gas cell.

6. The atomic oscillator according to claim 1, further comprising:

an optical member to convert the light emitted from the light source into collimated light along an optical axis;

wherein

the optical member is provided between the light source and the gas cell.

7. The atomic oscillator according to claim 1, further comprising:

a diffusion member to diffuse the light emitted from the light source;

wherein

the diffusion member is provided between the light source and the gas cell.

8. The atomic oscillator according to claim 1, wherein the optical axis of the light source deviates from a central axis of the gas cell.

16. An electronic device, comprising the atomic oscillator according to claim 1.

17. The electronic device according to claim 16, wherein a width of the radiation region of the light source increases in the internal space toward the light detecting portion.

18. The electronic device according to claim 16, wherein the gas cell comprises:

an entrance window at which the light from the light source enters the gas cell, the entrance window being provided at a proximal end of the gas cell relative to the light source;

an exit window at which the light passing through the internal space exits the gas cell toward the light detecting portion, the exit window being provided at the distal end of the gas cell; and

a lateral wall that defines the entrance window and the exit window; and

the lateral wall includes a light blocking portion defined by a light absorbing member.

9. An atomic oscillator, comprising:

a light source;

a gas cell including an internal space in which an alkali metal atom is sealed; and

a light detecting portion to detect light emitted from the light source and passing through the gas cell;

wherein

a portion of the light emitted from the light source enters the gas cell at a proximal end relative to the light source.

10. The atomic oscillator according to claim 9, wherein the gas cell comprises:

an entrance window at which the light from the light source enters the gas cell, the entrance window being provided at a proximal end of the gas cell relative to the light source;

an exit window at which the light passing through the internal space exits the gas cell toward the light detecting portion, the exit window being provided at the distal end of the gas cell; and

a lateral wall that defines the entrance window and the exit window; and

the lateral wall includes a light blocking portion defined by a light absorbing member.

11. The atomic oscillator according to claim 10, wherein the light blocking portion has a light absorption coefficient of about 23 cm⁻

1 or more.

12. The atomic oscillator according to claim 9, further comprising:

a light blocking member to block a portion of the light emitted from the light source so that the portion of the light does not enter the gas cell;

wherein

the light blocking member is provided between the light source and the gas cell.

13. The atomic oscillator according to claim 9, further comprising:

an optical member to convert the light emitted from the light source into collimated light along an optical axis;

wherein

the optical member is provided between the light source and the gas cell.

14. The atomic oscillator according to claim 9, further comprising:

a diffusion member to diffuse the light emitted from the light source;

wherein

the diffusion member is provided between the light source and the gas cell.

15. The atomic oscillator according to claim 9, wherein the optical axis of the light source deviates from a central axis of the gas cell.

19. An electronic device, comprising the atomic oscillator according to claim 9.

20. The electronic device according to claim 19, wherein the gas cell comprises:

an entrance window at which the light from the light source enters the gas cell, the entrance window being provided at a proximal end of the gas cell relative to the light source;

an exit window at which the light passing through the internal space exits the gas cell toward the light detecting portion, the exit window being provided at the distal end of the gas cell; and

a lateral wall that defines the entrance window and the exit window; and

the lateral wall includes a light blocking portion defined by a light absorbing member.