JPH06152407A - Rubidium gas cell for rubidium atom oscillator - Google Patents

Abstract

PURPOSE:To provide rubidium gas cell for a rubidium atom oscillator which can reduce Q inside a cavity part, eliminates the loss of light and can move the retaining of rubidium metal to the outside of a cavity part. CONSTITUTION:The rubidium gas cell is provided with duplex cylinder structure communicating a first small-diameter cylindrical part 10 with a second large- diameter cylindrical part 20, and a circular dielectric panel 8' is provided on the outer periphery of the first cylindrical part 10. Therefore, the Q inside a cavity part 1 can be reduced, the stability of a frequency against microwave level fluctuation can be improved, and the loss of light caused by the dielectric panel 8' is eliminated, as well. On the other hand, the rubidium gas cell is provided with a hollow projecting part 20 protruding from a part of the outer wall of the second cylindrical part 20 to the outside of the cavity part 1. Therefore, the hollow projecting part 3 is cooled down, undeseired rubidium metal is stocked at the hollow projecting part 3, and the diffusion of rubidium metal can be prevented, thus, characteristic stabilized for a long period can be provided. Further, the length of the cavity can be shortened by adding the dielectric panel 8'.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubidium gas cell used for an optical microwave resonance part of a rubidium atomic oscillator.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a rubidium gas cell 2 in which two large and small cylindrical shapes are coaxially connected in series is inserted in a cavity 1 in a rubidium atomic oscillator, and the cavity 1 When the cavity length inside is shortened, the dielectric plate 12 is inserted between the light transmission hole 11 of the cavity portion 1 and the rubidium gas cell 2. In the figure, 7 is a light receiving element.

[0003]

When only the rubidium gas cell 2 is inserted into the cavity portion 1 of the rubidium atomic oscillator, the inside Q of the cavity portion 1 becomes high, so that the inside of the cavity portion 1 over time becomes high. There is a drawback that the microwave level change becomes large and the long-term frequency stability deteriorates.

If the dielectric plate 12 is inserted between the light transmission hole 11 and the rubidium gas cell 2 in order to shorten the cavity length in the cavity portion 1, light loss due to the dielectric plate 12 cannot be avoided. However, there is a drawback that the loss of light reaching the rubidium gas cell 2 increases and the signal strength decreases. Further, since the pool of the rubidium metal comes inside the cavity portion 1, the temperature of the pool portion of the rubidium metal rises,
When it diffuses in the rubidium gas cell 2 and is used for a long period of time, there is a drawback that the microwave level inside the cavity 1 is lowered.

A first object of the present invention is to provide a rubidium gas cell for a rubidium atomic oscillator, which can reduce the Q in the cavity portion and has no light loss.

A second object of the present invention is to provide a rubidium gas cell for a rubidium atomic oscillator, which can move unnecessary pools of rubidium metal to the outside of the cavity.

[0007]

According to the present invention, there is provided a first cylindrical shape having a first inner diameter and a first outer diameter, which has a disk-shaped face plate at one end and is open at the other end. A second inner diameter larger than the first inner diameter, and a circular face plate having a hole having a diameter equal to the first inner diameter at one end and a disc-shaped face plate at the other end. A second cylindrical portion having a second outer diameter larger than the first outer diameter, wherein the first and second cylindrical portions are arranged on the same axis. 1
In a rubidium gas cell for a rubidium atomic oscillator, wherein the other end of the cylindrical portion and the annular face plate at the one end of the second cylindrical portion are connected to each other, the rubidium gas cell is provided on the outer periphery of the first cylindrical portion. There is provided a rubidium gas cell for a rubidium atomic oscillator, comprising an annular dielectric plate having an inner diameter equal to the first outer diameter and an outer diameter equal to the second outer diameter.

Further, according to the present invention, the outer wall of the second cylindrical portion has a face plate at a protruding tip, and a hollow protruding portion whose inner space communicates with the inner space of the second cylindrical portion. A rubidium gas cell for a rubidium atomic oscillator, which is characterized in that it is formed.

Further, according to the present invention, the hollow protrusion is
A rubidium gas cell for a rubidium atomic oscillator is obtained, which penetrates the annular dielectric plate from the annular face plate of the second cylindrical portion and projects outward.

Further, according to the present invention, the annular dielectric plate is provided on the outer periphery of the first cylindrical portion while being in contact with the annular face plate of the second cylindrical portion. A rubidium gas cell for a rubidium atomic oscillator is obtained.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a front view of a rubidium gas cell 2'for a rubidium atomic oscillator according to an embodiment of the present invention, and FIG. 2 is a sectional view of the rubidium gas cell 2'when it is loaded inside a cavity 1. Is.

The rubidium gas cell 2'includes first and second cylindrical portions 10 and 20. The first cylindrical portion 10 has a disc-shaped face plate 4 at one end, is open at the other end, and has a first inner diameter and a first outer diameter.
The second cylindrical portion 20 has an annular face plate 5 having a hole having a diameter equal to the first inner diameter at one end and a disc face plate 6 at the other end.
And has a second inner diameter larger than the first inner diameter and a second outer diameter larger than the first outer diameter. An annular shape of the other end of the first cylindrical part 10 and the one end of the second cylindrical part 20 is arranged so that the first and second cylindrical parts 10 and 20 are arranged on the same axis. Is connected to the face plate 5.

The rubidium gas cell 2'is made of glass in which rubidium metal is enclosed, and a part of the outer wall of the rubidium gas cell 2'is fixed to the inner wall of the cavity 1.

The annular dielectric plate 8'has an inner diameter equal to the first outer diameter and an outer diameter equal to the second outer diameter, and the annular dielectric plate 8'has a second outer diameter. It is provided on the outer periphery of the first cylindrical portion 10 in a state of being in contact with the annular face plate 5 of the cylindrical portion 20.

By inserting the dielectric plate 8 ', the cavity length in the cavity portion 1 can be shortened. Further, the dielectric plate 8'made of Teflon material (dielectric) or the like can lower the Q in the cavity portion 1 and improve the frequency stability with respect to microwave level fluctuation.

The annular face plate 5 of the second cylindrical portion 20 has a face plate 40 at the projecting tip, and a hollow protrusion 3 is formed so that the inner space communicates with the inner space of the second cylindrical portion 20. Has been done. The hollow protruding portion 3 penetrates the annular dielectric plate 8 ′ from the annular face plate 5 of the second cylindrical portion 20 and projects outward. The protruding tip of the hollow protruding portion 3 can extend to the outside of the cavity portion 1. Therefore, the protruding tip of the hollow protruding portion 3 is sufficiently cooled, and unnecessary rubidium metal is collected in the protruding tip portion of the hollow protruding portion 3.

Since the rubidium gas cell 2'receives light and absorbs the light, and then detects the passing light by the light receiving element 7, it is necessary to configure the light passing surface by the minimum necessary. In the example, only two face plates 4 and 6 are used. Therefore, it is possible to minimize the loss of light.

[0019]

As described above, the rubidium gas cell according to the present invention has a double cylindrical structure composed of a small-diameter first cylindrical portion and a large-diameter second cylindrical portion, and has a first cylindrical portion. Since an annular dielectric plate is provided on the outer periphery of the dielectric plate, Q in the cavity can be appropriately lowered, frequency stability against microwave level fluctuation can be improved, performance can be improved, and dielectric plate 8 There is no loss of light due to ´.

Further, the rubidium gas cell according to the present invention has a structure having a hollow projecting portion projecting from a part of the outer wall of the second cylindrical portion, and even if the rubidium gas cell is provided with a dielectric plate, the hollow projecting portion is hollow. Since the portion is cooled, an unnecessary pool of rubidium metal can be transferred to the outside of the cavity portion, diffusion of rubidium metal can be prevented, stable characteristics can be obtained for a long time, and quality and characteristics can be improved.

Further, since the dielectric plate is added to the rubidium gas cell, the cavity length inside the cavity can be shortened.

[Brief description of drawings]

FIG. 1 is a front view of a rubidium gas cell for a rubidium atomic oscillator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which the rubidium gas cell of FIG. 1 is loaded inside a cavity.

FIG. 3 is a cross-sectional view showing a state in which a conventional rubidium gas cell is loaded inside a cavity.

[Explanation of symbols]

 1 Cavity Part 2 Rubidium Gas Cell 2'Rubidium Gas Cell 3 Hollow Projection Part 4 Disc Face Plate 5 Annular Face Plate 6 Disc Face Plate 7 Light Receiving Element 8'Dielectric Plate 10 First Cylindrical Part 11 Light Transmission Hole 12 Dielectric plate 20 Second cylindrical portion 40 Face plate

Claims (4)

[Claims] 1. A first cylindrical portion having a disk-shaped face plate at one end and an opening at the other end and having a first inner diameter and a first outer diameter; and a first cylindrical portion equal to the first inner diameter. A ring-shaped face plate having a hole of a diameter at one end, and a disc-shaped face plate at the other end, and a second inner diameter larger than the first inner diameter and a first outer diameter larger than the first outer diameter. A second cylindrical portion having an outer diameter of 2, and the other end of the first cylindrical portion so that the first and second cylindrical portions are arranged on the same axis. In the rubidium gas cell for a rubidium atomic oscillator, which is connected to the annular face plate at the one end of the second cylindrical portion, the rubidium gas cell for the rubidium atomic oscillator is provided on the outer periphery of the first cylindrical portion, and is equal to the first outer diameter. Rubidium atomic oscillation characterized by including an annular dielectric plate having an inner diameter and an outer diameter equal to the second outer diameter Rubidium gas cell for dexterity. 2. A hollow projecting portion is formed on an outer wall of the second cylindrical portion, the hollow projecting portion having a face plate at a projecting tip and having an inner space communicating with the inner space of the second cylindrical portion. A rubidium gas cell for a rubidium atomic oscillator according to claim 1. 3. The hollow projecting portion projects outward from the annular face plate of the second cylindrical portion through the annular dielectric plate. And 2
A rubidium gas cell for a rubidium atomic oscillator according to any one of 1. 4. The annular dielectric plate is provided on the outer periphery of the first cylindrical portion while being in contact with the annular face plate of the second cylindrical portion. The rubidium gas cell for a rubidium atomic oscillator according to any one of claims 1, 2 and 3.