JPH032845A - Optical exclusive or device - Google Patents

Abstract

PURPOSE:To allow the high-speed computation of exclusive OR by constituting the above device of a double refractive material which is changed in refractive index by the intensity of input light and an optical resonator which houses the double refractive material and has the resonance wavelength made coincident with the wavelength when the intensities of the plural beams of the input light vary. CONSTITUTION:The double refractive material 11 having the Kerr effect to cause the refractive index to be changed by the intensity of the input light is housed in the optical resonator. The refractive index of the double refractive material 11 varies with the intensity totaling the intensities of the input light M, N and, therefore, the resonance wavelength by the double refractive material 11 and 1st, 2nd half mirrors 12, 13 changes. The intensity totaling the intensities of the input light M, N, therefore, attains P1 or intensity P3 if the intensities of the input light M, N are of the same level, i.e. a high level or low level and, therefore, the wavelength of the input light and the resonance frequency of the resonator vary. The transmittance of the resonator is consequently lowered and the output light Y is brought to the low level. The output light Y, however, attains the high level in the case of the levels at which the intensities of the input light M, N vary. The high-speed computation of the exclusive OR is executed in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an optical exclusive OR device used in optical information processing, optical communications, and the like.

Prior Art No. 4 is a block diagram showing the configuration of a conventional exclusive OR device.

In FIG. 4, reference numeral 1 denotes a first AND circuit, which has a logic input obtained by inverting logic input A and a logic input B as inputs.

Reference numeral 2 denotes a second AND circuit, which receives the logic input A and the logic input obtained by inverting the logic input B.

3 indicates an OR circuit; Second AND circuit 1.2
The logic outputs C and D of are used as logic inputs and a logic output X is output.

FIG. 5 is a diagram showing truth values of the exclusive OR device.

In FIG. 5, H indicates high level and L indicates low level.

Next, the operation will be explained.

In FIG. 4, logic inputs A and B are both at the same level,
That is, in the case of high level or low level, the first.
Since the logic outputs C and D of the second AND circuits 1 and 2 are both at a low level, the logic output X is at a low level.

However, if logic inputs A and B are at different levels, that is, logic input A is high level and logic input B is low level,
Or, if logic input A is low level and logic input B is high level, the first. Since either of the logic outputs C and D of the second AND circuits 1 and 2 becomes high level, the logic output
is at a high level.

Problems to be Solved by the Invention However, in the above-mentioned conventional exclusive OR device, the first
．． Since the second AND circuits 1 and 2 and the OR circuit 3 are composed of electronic circuits, the operating speed limit is several Gb.
/s.

The present invention is intended to solve these conventional problems, and aims to provide an optical exclusive OR device that can perform exclusive OR operations at high speed.

Means for Solving the Problems In order to achieve the above object, the present invention includes a birefringent material whose refractive index changes depending on the intensity of input light, and a birefringent material that accommodates this birefringent material so that when the intensities of a plurality of input lights differ. It is composed of an optical resonator whose resonant wavelength matches the wavelength of .

Therefore, according to the present invention, when the intensities of a plurality of input lights are the same, the resonant wavelength of the optical resonator deviates from the wavelength of the input light due to a change in the refractive index of the birefringent material.
The light is blocked and the output light becomes low level.

However, when the intensities of the plurality of input lights are different, the resonant wavelength of the optical resonator matches the wavelength of the input light, so the output light becomes high level.

Embodiment FIG. 1 is a block diagram showing an optical exclusive OR device according to one embodiment of the present invention.

In FIG. 1, 11 is a birefringent material such as LiNbO3, which has a Kerr effect whose refractive index changes depending on the intensity of input light, 12 is a first half mirror to which input lights M and N are supplied, and 13 is an output light. A second half mirror that outputs Y is shown, and the first and second half mirrors 12 and 13 constitute an optical resonator, and within this optical resonator, a birefringent material 11
is accommodated.

FIG. 2 is a characteristic diagram showing the relationship between the intensity of the input light and the refractive index of the birefringent material, and FIG. 3 is a characteristic diagram showing the relationship between the wavelength of the input light and the transmittance of the optical resonator.

In Figures 2 and 3, P blindness, P2. P3 indicates the total intensity of the input lights M and N, and Pl indicates the input light M,
When N are both low level, P2 is a case where one of the input lights M and H is low level and the other is high level, and P3 is a case where both input lights M and N are high level.

λ1. λ2. λ3 indicates the resonance wavelength (long resonance frequency), and the resonance wavelength λ1 is the intensity P! , the resonant wavelength λ2 is the intensity P2
In this case, the resonance wavelength λ3 is the intensity P3.

Note that the resonant wavelength λ2 of the optical resonator is the input light M.

This is to match the wavelength of N.

Next, the operation of the above embodiment will be explained.

In the above embodiment, the refractive index of the birefringent material 11 changes depending on the total intensity of the input lights M and N, as shown in FIG. Second
The resonance wavelength caused by the half mirrors 12 and 13 changes as shown in FIG.

Therefore, when the intensities of the input lights M and N are at the same level, that is, high level or low level, the input lights M and N
The total intensity becomes Pl or intensity P3, and since the wavelength of the input light and the resonant frequency of the resonator are different, the transmittance of the resonator decreases and the output light Y becomes a low level.

However, if the intensities of the input lights M and H are at different levels,
Since the total intensity of the input lights M and N becomes the intensity P2, the wavelength of the input light and the resonant frequency of the resonator match, so the output light Y becomes high level.

In this way, according to the above embodiment, the two input lights M, N
Obtain an optical exclusive OR device in which when the intensities of the two input lights M and N are at different levels, the output light Y is at a high level, and when the intensities of the two input lights M and N are both at the same level, the output light Y is at a low level. be able to.

Furthermore, since the birefringent material 11 whose refractive index changes depending on the intensity of input light is used, the calculation speed is faster than that of an exclusive OR device configured with an electronic circuit.

Effects of the Invention As is clear from the above-mentioned embodiments, the present invention is configured so that the exclusive OR operation can be performed using optical signals, and therefore has the advantage that the exclusive OR operation can be performed at high speed.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an optical exclusive OR device according to an embodiment of the present invention, Fig. 2 is a characteristic diagram showing the relationship between the intensity of input light and the refractive index of a birefringent material, and Fig. 3 is an optical resonance diagram. Figure 4 is a block diagram showing the configuration of a conventional exclusive OR device, and Figure 5 is a diagram showing the truth value of the exclusive OR device. be. 11... Birefringent material, 12... First half mirror
13...2nd half mirror Agent's name Patent attorney Shigetaka Awano and 1 other person Fig. Input Light I Enter 2 Enter 3 Input light〉4 sorrow

Claims (1)

[Claims] A birefringent material whose refractive index changes depending on the intensity of input light,
An optical exclusive OR device that contains this birefringent material and includes an optical resonator whose resonant wavelength matches the wavelength when one of two input lights having the same wavelength is input.