CN1614368A - Laser energy meter with quick responded and wide spectrum band impulsives - Google Patents

Abstract

An energy meter is composed of transducer probe connected with one end of signal connection line, signal connection line and display instrument connected with another end of signal connection line. The meter is featured as applying oxide film in perovskite structure at molecular formula of ABO3 as material of transducer probe, applying fast circuit and D-A converting device in display instrument to convert induced voltage peak value to be incoming laser energy and to display it out in digital form.

Description

The wide spectrum pulsed light of fast-response laser energy meter

Technical field:

The present invention relates to a kind of wide spectrum pulsed light of fast-response laser energy meter that is used to measure pulsed light, laser energy or power, belong to sensor technology and field of test instrument.

Background technology:

At present, traditional laser, photo measure mainly are divided into photon type measuring instrument and calorimetric type measuring instrument two big classes.The photon type measuring instrument is based on incident light in the semiconductor material to the exciting of charge carrier, and as the generation of electron-hole pair, measures incident light.This class detector has very fast time response usually, but is subjected to be with or the restriction of energy level, is not easy usually to work in very wide spectral range.Calorimetric type detector such as Bolometer then are the variations that has physical quantity (as resistance) when absorbing heat, by to the monitoring of physical index and the measuring light radiation.This class device can be worked in very wide spectral range, but needs the long time to reach thermal equilibrium, so the response time is slow.Above-mentioned two class devices need apply bias voltage or bias current mostly, thereby cause the interference of dark current, thermonoise and so on, also are catabiotic devices simultaneously.

Summary of the invention:

The objective of the invention is to overcome the deficiency of prior art, and a kind of have concurrently simultaneously wide spectral response and fast time response are provided, and need not apply any bias voltage, bias current, save the energy, the wide spectrum pulsed light of the fast-response laser energy meter that sensitivity is higher.

The principle that the present invention is based on is: we find that the sull (see figure 2) of substrate preparation has laser induced chemical vapor deposition voltage effects and induced potential and incident light energy and is good linear relationship (see figure 3), based on this class new material and new effect, we design and have made the wide spectrum of this tool (0.19～11 μ m), fast-response (μ s, ns magnitude) pulsed light laser energy meter.The thermoelectric tensor of membraneous material after coordinate transform is:

Then have induced potential to produce in the x of material direction when to film surface irradiation short-pulse laser, its time relation is:

$U\left(t\right)=\frac{{\mathrm{\α}}_0\mathrm{El}\sin \left(2\mathrm{\α}\right)}{4\mathrm{d\ρ}{c}_0\sqrt{\mathrm{\πDt}}}(S_{\mathrm{ab}}-S_c)(e^{-\frac{{\mathrm{\δ}}^2}{4\mathrm{Dt}}}-e^{-\frac{d^2}{4\mathrm{Dt}}})$

We prove that induced potential is the function of a time, and is asymmetric.We are in 248nm (ultraviolet light)～1064nm (infrared light) wavelength coverage, and measurement result shows: the peak value of induced potential and the linear (see figure 3) of incident pulse laser energy.Therefore can represent the energy of incident laser with the area of the peak value of induced potential or induced potential waveform, the making energy meter.

Incident laser energy, between its induced potential that causes, and the data that finally demonstrate with digital form are finished by surveying electronic circuit, mould/number conversion and energy scaling three parts.Can be at different optical maser wavelengths, different membraneous materials is proofreaied and correct the relation between incident light energy and the induced potential peak value, and writes chip circuit, thereby makes things convenient for different wave length and different time response or other different measurements that require.

Technical scheme of the present invention is: this energy meter is made up of the sensor probe (1) that is connected with signal connecting line (2) one ends, signal connecting line (2), the Displaying Meter (3) that is connected with signal connecting line (2) other end; Wherein:

1. the material of sensor probe (1) employing is a sull, and oxide film material is a perovskite structure, forms ABO ₃Molecular formula; A is the combination of trivalent rare earth or trivalent rare earth and divalent alkaline-earth metal, and B is the transition-metal ion of Mn, Co, the variable valence state of Fe; Such sull has anisotropic thermoelectric tensor (Seebeck tensor), as S _Ab=S _c, S wherein _Ab, S _cRepresent respectively in the ab face and the c direction on thermoelectric tensor unit.

2. signal connecting line (2) is the shielding line of band BNC connector;

3. Displaying Meter (3) is for to be converted into incident laser energy with a kind of fast circuit and corresponding digiverter with the induced potential peak value, and shows with digital form.

The invention has the beneficial effects as follows: have response time fast (can reach microsecond and nanosecond order), spectral range wide (0.19～11 micron) and do not need advantage such as bias supply, can accurately measure pulsed light, laser energy or the power of microsecond and nanosecond order, and can save the energy.

Description of drawings:

Fig. 1 is the wide spectrum pulsed light of a fast-response laser energy meter synoptic diagram.

Fig. 2 is the ABO that grows on the inclination single crystalline substrate ₃Film and coordinate synoptic diagram.

Fig. 3 is pulsed laser energy and LaCaMnO under 1.064 mum wavelengths ₃The relation curve of induced potential on the film.

Fig. 4 is fast circuit and corresponding digiverter synoptic diagram.

Embodiment:

Embodiment: at inclination substrate surface growing oxide film, make metal electrode at the film two ends, gather induced potential signal, the line linearity match of going forward side by side under the different wave length pulsed light, in match relation input single-chip microcomputer by photoetching process; At protection of film surface evaporation and anti-reflection film, finish the probe encapsulation simultaneously; To pop one's head in by the shielded signal wire that has BNC connector then is connected with Displaying Meter, carries out calibrating indicating instrument and environmental experiment, can finish complete machine and make.When the laser pulse width of incident was very narrow, the induced potential peak value was directly proportional with projectile energy (power), with a kind of fast circuit and corresponding digiverter the induced potential peak value is converted into incident laser energy, and shows with digital form.

The present invention is equipped with the power that this instrument of chopper also can be measured continuous light, laser.Use proof, the every index of the present invention all reaches designing requirement.

Claims (2)

1, the wide spectrum pulsed light of a kind of fast-response laser energy meter is made of sensing probe measuring sensor (1), signal connecting line (2), the Displaying Meter (3) that is connected with signal connecting line (2); It is characterized in that:

(1) sensing probe measuring sensor (1) is the sull that is grown on the inclination substrate, has perovskite structure, forms ABO ₃Molecular formula, wherein A is the combination of trivalent rare earth or trivalent rare earth and divalent alkaline-earth metal, and B is a magnesium-yttrium-transition metal, as the transition-metal ion of Mn, Co, the variable valence state of Fe;

(2) be provided with fast circuit and corresponding digiverter in the Displaying Meter (3), the induced potential peak value be converted into incident laser energy, and show with digital form.

2. by the wide spectrum pulsed light of the said fast-response of claim 1 laser energy meter, it is characterized in that its response time can reach microsecond or nanosecond order; Measure at 0.19～11 micron paired pulses, continuous laser simultaneously; And be connected to Displaying Meter (3) by signal connecting line (2) and show measurement result.

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