JPH065796B2 - A device that converts light into radio waves - Google Patents

Description

TECHNICAL FIELD The present invention relates to a device for directly converting light into radio waves.

BACKGROUND OF THE INVENTION No device is currently known that directly converts light into radio waves.

If light can be directly converted into ultra-high frequency, it can be effectively used not only for high-speed information processing and transmission such as frequency locking and intermediate frequency detection but also for wireless power transmission.

However, none of them has been tried so far.

(Object of the Invention) An object of the present invention is to provide a device that directly converts light into radio waves.

It should be noted that the light referred to here is light having a wavelength as long as a technically effective reflection surface can be formed, but mainly refers to light from the ultraviolet region to the infrared region.

Similarly, the radio wave referred to here is an electromagnetic wave having an arbitrary period as far as technically possible, but its main application range is mainly from the far infrared region to millimeter waves and microwaves.

(Structure of the Invention) In order to achieve the above-mentioned object, the device for converting light into a radio wave according to the present invention reflects an ultra-high frequency waveguide and the light formed on the inner wall surface or the surface of the inner wall surface of the ultra-high frequency waveguide. And a light source that makes light enter so that light is reflected back and forth between the metal reflection surfaces, and the waveguide can guide an ultra-high frequency corresponding to the round-trip cycle of the light. In addition, it is configured to convert incident light into a radio wave and output it.

According to the above configuration, it is possible to provide a novel device that can directly convert light into radio waves.

(Description of Examples) Hereinafter, the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a perspective view and a sectional view of a light incident part showing an embodiment of an apparatus for directly converting light into a radio wave using an ultra-high frequency waveguide according to the present invention. In addition, in order to facilitate understanding of the internal structure, it is shown partially broken.

A small hole 2a for introducing the incident light 1 is provided on the upper surface of the rectangular waveguide 2 for ultrahigh frequencies.

One end of the waveguide 2 is a reflection end face 3, and a tuner is provided if necessary.

The inner surfaces 4, 5 of the waveguide 2 form a pair of metallic mirror surfaces. The other end 6 of the super high frequency wave guide 2 forms an outlet for the radio wave converted from the converted light.

A cavity resonator or a detection diode is arranged at the other end 6 to confirm or take out the generation of radio waves.

Incident light 1 is introduced into the super-high frequency waveguide 2 through a small hole 2a provided in the super-high frequency waveguide 2, and the metallic mirror surfaces 4, 5 are introduced.
It can be reflected back and forth between.

Here, the principle of directly converting light into a radio wave according to the present invention will be briefly described.

The difference has to be provided by the reflecting surface, since when the light undergoes a 180 degree direction change at the metallic reflecting surface, the reflected light has a momentum opposite to that of the incident light. The reflection in this case is metallic reflection when the plasma frequency defined by the free electron density is higher than the frequency of incident light.

With ordinary metals, the plasma frequency is in the ultraviolet region and reflects infrared light and visible light.

In semiconductors, the plasma frequency is in the visible or infrared range and reflects infrared light.

In the present invention, the specular reflection material is selected according to the target wavelength as described above.

This momentum to be supplied is the collective polarization of the electrons in this embodiment where the reflective surface is metal.

Further, in the case of another structure in which the reflecting surface is a dielectric, it is due to the excitation of the optical vibration mode of the lattice atom.

It is preferable that the relaxation time of the polarization is long, and in that respect, collective electron polarization is suitable. In addition, a lower temperature is generally suitable in terms of operating efficiency.

When the light is reflected on the other surface, polarization of the reflection polarity occurs with a delay of the traveling time. For light traveling in a zigzag manner, this delay does not cause a slow wave effect in a traveling wave tube or the like, and can thereby be matched with the phase velocity of a radio wave traveling in the waveguide axis direction. This is nothing but phase matching. At this time, a practical microwave frequency (for example, 30 GHz) can be obtained. When phase matching is established, a momentum pulse generated inside free electrons in the mirror surface by light reflection constitutes a traveling electric field vector for a propagating electric wave, so that a radio wave can be generated. It can be seen from the figure that this electric field vector is generated for each wavelength of the radio wave at each reflection point on one surface and is deviated from the reflection point on the opposite surface by half a wavelength. In addition, as a practical problem, when radio waves or light are reflected at the end face of the waveguide and a wave traveling in a direction opposite to that described above occurs, it is prevented that the phase of the wave in the opposite direction is not adjusted for the tuner or the like. It is also necessary.

Therefore, in the device shown in FIG. 1, radio waves of the fundamental mode, for example, the TE mode, determined by the waveguide are generated by the periodic shock excitation.

This period is equal to the round-trip travel time of light, but of course it must be set so that it lies within the pass band that is the cutoff frequency of the waveguide.

The ultra-high frequency generated in this way is in the wavelength range of, for example, a millimeter wave, so that it can be guided or resonated by a cavity resonator and turned into a direct current by a diode.

The light reciprocating space need not be a space as in this embodiment, but may be a dielectric having an appropriate dielectric constant as described later.

Since the light reflecting surface forms a part of the waveguide, it is necessary to have a conductive portion. It is for this reason that the term metallic reflecting surface is used in the present invention.

FIG. 2 shows another embodiment in which a transparent dielectric material is arranged in the light reciprocating space.

FIG. 2 is a perspective view showing only a portion of the waveguide of the embodiment shown in FIG. 1 corresponding to a portion where light is incident.

A protrusion 7 for adjusting the waveguide impedance and a transparent dielectric 8 for round-trip reflection of light are provided. The configuration of the other parts is the same as that described with reference to FIG.

FIG. 3 is a sectional view including a tube axis of a waveguide showing still another embodiment.

In this embodiment, the light incident from the small hole 2a of the waveguide 2 is successively reflected by the metallic reflection surfaces 4 and 5 of the waveguide along the tube axis and propagated in the opening direction of the waveguide 2. It is configured to be operated.

Thereby, the propagation velocity in the tube axis direction can be phase-matched between the light and the generated radio wave.

Since the speed at which the radio wave propagates in the tube axis direction is determined by the inherent dispersion relation, phase matching between the light and the radio wave is possible, and conversion can be performed repeatedly. This is especially effective for electromagnetic wave conversion of ultrafast pulse waveforms.

Of course, it is also possible to insert an electrical delay circuit between each reflection point if necessary.

It is also possible to set it as a reflection surface so that total reflection occurs at the interface of the dielectric placed inside the waveguide.

Various modifications can be made to the embodiment described above within the scope of the present invention.

In each of the above embodiments, the case of the TE mode is shown, but also in the case of other modes, it is preferable that the directions of the lines of electric force and the electronic polarization direction in each mode are made to coincide with each other.

Although each of the above embodiments utilizes a waveguide, other waveguides such as a strip structure can be used as well. At this time, the radio waves in the TEM mode are used, but the operation is the same.

(Explanation of Effect of the Invention) As described above, according to the present invention, it is possible to directly convert light into an ultra-high frequency.

This has never been attempted in the prior art. This makes it possible to provide a new device that is effective not only for high-speed information transmission processing such as frequency locking and intermediate frequency detection, but also for wireless power transmission and the like.

[Brief description of drawings]

FIG. 1 is a perspective view and a sectional view showing an embodiment of an apparatus for converting light into radio waves according to the present invention. FIG. 2 is a perspective view showing another embodiment of the device for converting light into radio waves according to the present invention. FIG. 3 is a perspective view showing still another embodiment of the device for converting light into radio waves according to the present invention. 1 ... Incident light 2 ... Ultra high frequency wave guide 3 ... Reflection end of ultra high frequency wave guide 4, 5 ... Metallic reflection surface 6 ... Ultra high frequency exit 7 ... Protrusion 8 ... Transparent dielectric

Claims (3)

[Claims] 1. An ultrahigh-frequency waveguide, an inner wall surface of the ultra-high-frequency waveguide, or an opposing metallic reflecting surface that reflects light formed on the surface of the inner wall surface, and light traveling back and forth between the metallic reflecting surfaces. A light source for making light incident so as to be reflected, the waveguide being capable of guiding an ultra-high frequency corresponding to the round-trip cycle of the light, and configured to convert incident light into a radio wave and output it. A device that converts light into radio waves. 2. The light from the light source is incident between the metallic reflecting surfaces so as to be repeatedly reflected along the direction of the generated radio wave, and phase matching is established between the light and the radio wave. A device for converting the light according to claim 1 into a radio wave. 3. The device for converting light into a radio wave according to claim 1, wherein the ultra-high frequency waveguide is a rectangular waveguide.