CN203909426U

CN203909426U - Light beam intensity modulator

Info

Publication number: CN203909426U
Application number: CN201420381566.9U
Authority: CN
Inventors: 励春亚
Original assignee: Xiangshan Xingqi Electric Appliance Technology Co Ltd
Current assignee: Xiangshan Xingqi Electric Appliance Technology Co Ltd
Priority date: 2014-07-01
Filing date: 2014-07-01
Publication date: 2014-10-29
Anticipated expiration: 2024-07-01

Abstract

The utility model relates to a light beam intensity modulator. The light beam intensity modulator comprises piezoelectric ceramic (1), a knife edge (2) and two convex lenses (3), wherein the knife edge (2) is mounted at the upper end of the piezoelectric ceramic (1); the two convex lenses (3) are arranged on two sides of the knife edge (2); the position of a knife point of the knife edge (2) is folded with a light beam gathering focus which transmits through the convex lenses (3); the piezoelectric ceramic (1) is high-precision piezoelectric ceramic; a focus between the convex lenses (3) is folded with the light beam gathering focus; a collimating lens is arranged at the front end of the light beam intensity modulator; mono-mode optical fiber is arranged at the front end of the collimating lens. The light beam intensity modulator avoids the interference of power frequency and has good linearity and frequency response; with the combination of a micro-motion function of a micro displacement effect, the modulation signal precision is high.

Description

Beam intensity modulator

Technical field

The utility model relates to a kind of piezoelectric ceramics that adopts and light beam is carried out to the device of intensity modulated, relates in particular to a kind of beam intensity modulator, belongs to piezoelectric ceramics field.

Background technology

Laser Modulation refers to be overregulated human wants information exchange and control is added on laser wave.Laser beam has the unrivaled temporal coherence of other light beams and spatial coherence, and is easy to modulation, adds that laser light wave frequency is high, and energy transmission of information amount is very large.Laser-beam divergence angle is very little simultaneously, and luminous energy high concentration is convenient to again maintain secrecy when guaranteeing propagation distance, so laser is the ideal carrier that optical information transmits.

Utilize acousto-optic modulator to realize the intensity modulation to laser beam.Acousto-optic modulator is based on the work of acoustooptic effect principle.The periodicity that the density density of ultrasonic field medium distributes has formed acoustic grating, and pitch equals hyperacoustic wavelength.The light beam generation diffraction of incident, and diffraction intensity and hyperacoustic intensity is directly proportional, and utilizes this principle to realize the modulation to laser beam.

Utilize the modulation of loudspeaker to laser beam intensity.Loudspeaker utilizes tone currents to change the alternating magnetic field producing and forces voice coil loudspeaker voice coil to produce mechanical vibration, drive vibrating diaphragm vibration, and the frequency of vibrating diaphragm vibration is directly proportional to the frequency of tone currents.According to this principle, select frequency of operation loudspeaker on the low side, vibrating diaphragm can alternative method function piezoelectric ceramics micrometric displacement topworks in a), drive chopper to complete the intensity modulated to light beam, the precision that is this kind of method frequency stability and displacement control is limited.

Utility model content

In order to overcome the deficiencies in the prior art, resolve the problem of prior art, make up the deficiency of existing existing product in the market.

The utility model provides a kind of beam intensity modulator, beam intensity modulator comprises piezoelectric ceramics, is arranged on the edge of a knife of piezoelectric ceramics upper end, be arranged on two convex lens of edge of a knife both sides, the position of tool tip of the described edge of a knife converges focus with the light beam of process convex lens and overlaps.

Preferably, above-mentioned piezoelectric ceramics is High Precision Piezoelectric Ceramic.

Preferably, the focus of above-mentioned convex lens converges focus with light beam and overlaps.

Preferably, above-mentioned beam intensity modulator front end is provided with collimation camera lens.

Preferably, above-mentioned collimation camera lens front end is provided with single-mode fiber.

The beam intensity modulator that the utility model provides has been evaded the interference of power frequency, has good linearity and frequency response, coordinates the fine motion function of micrometric displacement effect, and modulation signal precision is high.

Accompanying drawing explanation

Fig. 1 is the utility model structural representation.

Reference numeral: 1-piezoelectric ceramics; The 2-edge of a knife; 3-convex lens.

Embodiment

For the ease of those of ordinary skills, understand and implement the utility model, below in conjunction with the drawings and the specific embodiments, the utility model being described in further detail.

According to the feature of laser drift amount signal and the demand to modulation stability and precision, adopt piezoelectric ceramics to carry out intensity modulated to light beam, with evade that power frequency that 50HZ and frequency-doubled signal thereof bring is disturbed and beam propagation process in the noise introduced, concrete grammar as shown in Figure 1:

At light beam through single-mode fiber after elementary collimation, utilize collimation camera lens the pointolite of single-mode fiber outgoing to be become to the light source of parallel outgoing, in light path, utilize convex lens to be converged at focus, in device, fix a High Precision Piezoelectric Ceramic, and an edge of a knife is installed thereon, the remittance focal spot focusing that makes the edge of a knife just be positioned at light beam is cut, make light beam become the signal of alternation, after focus, separately put convex lens, making its focus and light beam converge focus overlaps, through second convex lens, light beam becomes again directional light like this.Utilize high drive power drives piezoelectric ceramics, make it to produce the flexible of constant frequency, thereby complete the cutting to beam focus, in order to evade the interference of power frequency, select the sinusoidal signal away from the 427HZ of power frequency interference here.Piezo-ceramic micro displacement unit utilizes the micrometric displacement effect that piezoelectric ceramics produces under extraneous electric field action to realize fine motion function, is divided into the flexible ceramic micro positioner of piezoelectricity that utilizes inverse piezoelectric effect and the Electrostrictive ceramic micropositioner that utilizes electrostrictive effect.The utility model adopts electrostriction micromotion device, and the range under ± 600 voltages drive is ± 6 μ m, has good linearity and frequency response.

In signal modulation, Chang Yiyi high frequency sinusoidal signal is as carrier signal, and a sinusoidal signal has amplitude, frequency, three parameters of phase place, can modulate these three parameters, is called amplitude modulation, frequency modulation and phase modulation.Due to the very high frequency of laser wave, while carrying out external modulation as required, frequency modulation and phase modulation are difficult to realize, so system adopts the method for amplitude modulation to modulate.Modulation is to give certain feature to measuring-signal, and this feature is provided by the signal as carrier, and Chang Yiyi high frequency sinusoidal signal or pulse signal are as carrier, and this carrier is called carrier signal.Be used for changing a certain parameter of carrier signal, as the signal of amplitude, frequency, phase place is called modulation signal, through the carrier signal of ovennodulation, be called modulated signal.

The embodiment of the above is better embodiment of the present utility model; not with this, limit concrete practical range of the present utility model; scope of the present utility model comprises and is not limited to this embodiment, and the equivalence that all shapes according to the utility model, structure are done changes all in protection domain of the present utility model.

Claims

1. a beam intensity modulator, it is characterized in that: described beam intensity modulator comprises piezoelectric ceramics (1), is arranged on the edge of a knife (2) of piezoelectric ceramics (1) upper end, be arranged on two convex lens (3) of the edge of a knife (2) both sides, the position of tool tip of the described edge of a knife (2) converges focus with the light beam of process convex lens (3) and overlaps.

2. beam intensity modulator according to claim 1, is characterized in that: described piezoelectric ceramics (1) is High Precision Piezoelectric Ceramic.

3. beam intensity modulator according to claim 2, is characterized in that: the focus of described convex lens (3) converges focus with light beam and overlaps.

4. beam intensity modulator according to claim 1, is characterized in that: described beam intensity modulator front end is provided with collimation camera lens.

5. beam intensity modulator according to claim 4, is characterized in that: described collimation camera lens front end is provided with single-mode fiber.