JPS62255836A - Sampling type time resolution photometric device - Google Patents

Abstract

PURPOSE:To simultaneously improve the utilization rate of a signal and the time resolution by providing plural pieces of sampling gates for a phenomenon of simple occurrence, and executing a measurement. CONSTITUTION:A light beam is transduced to an electric signal by a detector 1, amplified by a wide band amplifier 2, and thereafter, divided into plural (n) channels. On the other hand, a pulse from a main pulse generator 6 is brought to frequency-division 7 and a main pulse L is obtained. As a result, an excitation light source 8 is excited. Also, the pulse from the generator 6 becomes a saw tooth wave M through a save tooth wave pulse generator 6', and inputted to one terminal of a comparator 9. Moreover, a pulse from other pulse generator 10 becomes a saw tooth wave N of a gentle slope through a D/A converter and inputted to the other terminal of the comparator 9. In accordance with an output of this comparator 9, a sampling pulse S is generated, and each sampling gate G1-Gn is opened and closed in the course of a phenomenon of once. A level of a partial waveform which has been brought to sampling in this way is brought to integral holding A1-An, and thereafter, synthesized 3.

Description

Detailed Description of the Invention The present invention relates to a sampling type time-resolved photometry device for measuring transient light emission waveforms such as fluorescence and phosphorescence, and for lifetime measurement, and in particular, relates to a sampling type time-resolved photometer for measuring transient emission waveforms such as fluorescence and phosphorescence. This invention relates to a multi-sweep time-resolved photometry device that is capable of improving time resolution.

(Prior Art) The most common method for measuring fast transient light emission phenomena is a real-time direct observation method using a broadband oscilloscope. However, if the phenomenon is repeatable, sampling techniques can be applied. In the sampling method, output signals from a wideband detector are extracted and integrated through a sampling gate whose phase gradually shifts in synchronization with the repetition of a phenomenon, and each output is combined into a single waveform.

An example of a conventional sampling method is shown in Figures 1a and b. In FIG. 1a, (a) is the excitation main pulse pattern, and (b) is the transient phenomenon of fluorescence or phosphorescence to be measured. As shown in the same figure (c), one sawtooth wave m is generated in synchronization with the main pulse, while another sawtooth wave n with a very gentle slope is generated, and the two waveforms intersect. By generating a sampling pulse S like (d) at the time position and sampling the waveform (b), the individual extracted waveforms obtained as a result of sampling are synthesized again, and finally (e) The waveform to be measured is reproduced as shown in . That is, the observer can
), we will see the sampled output waveform over time.

Such sampling methods are often used because of their excellent signal-to-noise ratio, accuracy, and stability, despite the disadvantage of low signal utilization.

(Problem to be solved by the invention) However, when the above sampling method is applied to the lifetime measurement of phosphorescence, the lifetime measurement of relatively long-lived fluorescence, or the measurement of the emission waveform, the repetition rate This results in a significant reduction in signal utilization. If the width of the sampling gate is widened in order to improve the signal utilization rate, the temporal resolution will decrease. To avoid this, methods using high-speed A/D converters and multi-channel gate photon counting methods (for example, Japanese Patent Application Laid-Open No. 55-76919 by the present applicant) have been proposed, and good results have been obtained. However, each has problems in terms of price and temporal resolution. Furthermore, when trying to improve the time resolution, the number of channels increases, making the device more complicated and increasing the price.

Therefore, the purpose of the present invention is to eliminate the drawbacks of the above-mentioned conventional methods, and to
It is an object of the present invention to provide a sampling type time-resolved measurement device that can simultaneously improve both signal utilization rate and time resolution by providing a plurality of sampling gates for each phenomenon and performing measurement.

Ll and W (Means for Solving the Problems) In order to achieve the above object, the sampling type time-resolved measurement device according to the present invention synchronizes the output signal from the wideband detector with the reversal of the phenomenon. In a system that extracts and integrates through sampling gates whose phases gradually shift, and synthesizes each output into one waveform, multiple sampling gates are provided for one phenomenon, and these sampling gates are opened and closed to generate one waveform. It is characterized in that sampling is performed at multiple points during a single phenomenon, and each sampled data is combined to obtain one waveform.

The above sampling gate generates a sawtooth wave with a very gentle slope and a sawtooth wave that repeats multiple times between the periods of the main pulse, and generates a sampling pulse at the time position where these two sawtooth waves intersect. , it is preferable to open with this sampling pulse.

Signal processing in the present invention is performed analogously using a combination of a plurality of boxcar integrators and multiplexers, or digitally using a combination of an optical counter and a plurality of counters, depending on the incident light intensity. is preferable.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to FIG. 2 and subsequent figures.

First, a detailed explanation of the present invention will be given with reference to figures i2a and b. In figure 2a, as in the case of figure 1, (a) is the excitation main pulse L, and (b) is the fluorescence or phosphorescence to be measured. This is a transient phenomenon such as As in the conventional example, two sawtooth waves M and N are generated as shown in (c). Among them, N is a sawtooth wave with a very gentle slope like n in the conventional example, but unlike the conventional example, the other sawtooth wave M is not only one wave in synchronization with the main pulse, but also one wave between the periods of the main pulse. plural (n
) are generated. At the time position where these two waveforms M and N intersect, a sampling pulse S is generated as shown in (d). In other words, by generating n sampling pulses for one phenomenon and sampling the waveform (b), the individual extracted waveforms obtained as a result of sampling are rearranged and synthesized again, and the final result is The waveform to be measured is reproduced as shown in (e). As a result, the observer will see the sampled output waveform over time, as shown in FIGS. 2b (a)-(b).

Next, a configuration of signal processing for performing the above-described sampling and synthesis will be described. Note that the optical system and the like for measuring fluorescence and phosphorescence are not shown because they are the same as in the conventional example.

Figure 3 shows an example that is suitable for cases where the intensity of fluorescence or phosphorescence, that is, the light incident on the detector, is relatively strong. After being amplified by the amplifier 2, it is divided into a plurality of (n) channels. Each channel includes a gate G and an analog boxcar integrator A, and each output of these analog boxcar integrators A1 to An is connected via a multiplexer 3 to a display system 4 comprising a computer or the like.

Further, each gate G1 to Gn is connected to a gate control circuit 5.
It is opened and closed through. That is, the pulse from the main pulse generator 6 is divided by the frequency divider 7 to produce the main pulse L shown in FIG. 2a, which excites the excitation light source 8.

On the other hand, the pulse from the main pulse generator 6 passes through the sawtooth pulse generator 6°, becomes a sawtooth wave M, and is input to one terminal of the comparator 9. The pulses from another pulse generator lO are
A sawtooth wave N with a gentle slope is inputted to the other terminal of the comparator 9 via the D/A converter. The comparator 9 generates an output when the re-input levels match, and the sampling pulse generation circuit 11 generates the sampling pulse S in response to the comparator output, which causes the sampling pulse S to be generated during one phenomenon via the game control 5. Each game) Open and close G l - G n. The level of each partial waveform sampled in this way is determined by the corresponding analog boxcar integrator B1 to Bn.
After being integrated and held at , the waveforms are synthesized via the multiplexer 3 and the waveform to be measured by the display system 4 is synthesized and reproduced.

Figure 4 shows an example suitable for fluorescence or phosphorescence, that is, when the intensity of the light incident on the detector is very weak, and the light is converted into an electrical signal by the detector 12, such as a photomultiplier for photon counting. After being amplified by the high-speed pulse amplifier 13, the signal level is discriminated by the discriminator 14, and the level-converted signal output is divided into a plurality of (n) channels by 15. Each channel includes an AND forming a gate and a counter C, and each gate (ANDI to ANDn) is opened by inputting a sampling pulse similar to the above, and while the gate is open, each sampled portion is The number of photons corresponding to the waveform level is determined by each counter Cl.
w Stored in Cn.

Next, the stored values of the counters c1 to Cn are called up by an instruction from a signal processing system 18 consisting of a computer or the like, and the composite value to be measured is reproduced.

It is preferable to control the operation of both the configurations shown in FIGS. 3 and 4 by a computer. In this case, first, steady light is input and correction coefficients are determined in advance so that the gain of each channel is constant. All you have to do is multiply the measured value by that coefficient.

(Effects of the Invention) As described above, according to the present invention, a multi-sweep type is adopted in which a plurality of (n) sampling gates are provided for one phenomenon to perform measurement, so that it is possible to perform measurements without reducing the time resolution. A sampling-type time-resolved measuring device is obtained in which the signal utilization rate, which was a drawback in the sampling method described above, can be improved by n times, and furthermore, the time resolution can be further improved by limiting the number of channels.

[Brief explanation of drawings]

Figures 1a (a) to (e) and b are waveform diagrams for explaining the conventional method, and Figures 2a (a) to (e) and b are for explaining the sampling type time-resolved measuring device according to the present invention. FIG. 3 is a diagram showing an example of a signal processing operation configuration, and FIG. 4 is a diagram showing an example of a signal processing configuration. 1.12. ,,detector,380. multiplexer, 5.
,,gate control circuit,6.1°93. pulse generator, 810. Excitation light source, 9. , comparator, 11. ,, sampling pulse generation circuit, A
13. Analog block car planter, G. AND, , sampling gate, L21. Main pulse for excitation, M, , sawtooth wave that repeats multiple times during one event, N90. A sawtooth wave with a gentle slope. Applicant: JASCO Corporation Agent: Yuki Maruyama
Male Procedural Amendment (Method) July 23, 1986 Michibe Uga, Commissioner of the Patent Office 1. Indication of the case 1986 Patent Application No. 098692 2. Title of the invention: Sampling type time-resolved photometer. Patent Applicant Address: 2967 Ishikawa-cho, Hachioji-shi, Tokyo 5 Name Japan Bunko Industries Co., Ltd. Representative Director: Nao Miyazaki 4, Agent: 108 Address: 3-25-27-1208 Takanawa, Minato-ku, Tokyo No. June 4, 1986 (June 24 of the same year) - 1-6 Subject of amendment Description and drawings 7, contents of amendment (1) "1st & ( stomach)
~ (e) and b)'' and ``28 (a) ~ (e) and b'' are referred to as ``Figure 1 (a) and (b) J'' and ``Figure 2 (a) and (b)''. Correct each. (2) Add corrected drawings as shown in the attached sheet.

Claims (3)

[Claims] (1) In a sampling type time-resolved photometry device that extracts and integrates the output signal from a wideband detector through a sampling gate whose phase gradually shifts in synchronization with the repetition of a phenomenon, and synthesizes each output into a single waveform. , multiple sampling gates are provided for one phenomenon, these sampling gates are opened and closed to perform sampling at multiple points during one phenomenon, and each sampling data is synthesized to obtain one waveform. A sampling type time-resolved photometry device characterized by: (2) Generate a sawtooth wave with a very gentle slope and a sawtooth wave that repeats multiple times between the periods of the main pulse, generate a sampling pulse at the time position where these two sawtooth waves intersect, and perform this sampling. 2. The sampling type time-resolved photometry device according to claim 1, wherein said sampling gate is opened by a pulse. (2) The sampling type time-resolved photometry device according to claim 1, wherein signal processing is performed in an analog manner using a combination of a plurality of boxcar integrators and multiplexers. (3) The sampling type time-resolved photometry device according to claim 1, wherein signal processing is performed digitally using a combination of a photon counting device and a plurality of counters.