JPH01239434A - Optical detecting device - Google Patents

Abstract

PURPOSE:To improve the resolution of sample detection and to accurately measure the intensity distribution by converging scattered light which is passed through a sample by a photodetection lens and forming an image on an image element, and performing comparative arithmetic as to the photodetection position and photodetection intensity. CONSTITUTION:The light beam 11 from a laser 1 becomes a parallel light beam 13 with width through cylindrical lenses 2 and 3, and this parallel light beam crosses a sample surface 4 and is scattered by samples A and B. Scattered light beams 201 and 202 are converged by a stop 5 and a converging lens 6 to form its image on the image element 9. Here, light which is scattered in fine-angle directions around the optical axis and an unscattered light component are converged by the converging lens 6 and cut off by a shield plate 7 provided at the focus position. Then the scattered light which forms the image on the element 9 indicates the intensity distribution corresponding to the kind of the samples and a density distribution. Consequently, the resolution of the sample detection is improved and the intensity distribution is accurately measured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a technique for detecting the passing position of a sample passing on a certain straight line, and relates to an optical detection device suitable for measuring the position of a vfIC sample.

[Conventional technology]

Conventional photometry devices, for example, as described in Japanese Patent Application Laid-Open No. 60-196647, have a light beam that measures one point on the test R surface.
Irradiate the point 29. The secondary light that has passed through the sample surface t1'' is sent to the spectrometer.At this time, the sample surface is subjected to vibration control and oscillates at a constant cycle for 2 hours, and the position of the sample on the sample surface cannot be detected. This was done by integrating the output from the spectrometer over a fixed period of time using a sampling pulse synchronized with the sample surface vibration control signal.

In addition, the 70-cymemeter and optical particle detection device for detecting particles in a flow are disclosed in Japanese Patent Application Laid-open No. 61-270, for example.
As described in JP-A No. 659, JP-A No. 62-25256, and JP-A No. 62-25237, particles are made to flow down to the center of a flux flowing through a flow cell, and a laser beam is applied to a point in the flow. The path of the particles was detected by irradiating the particles with light and measuring the scattered light over time. fFVc
, in Japanese Patent Application Laid-Open No. 61-270639, 0° direction and 9
Scattered light and fluorescence emitted in the 0° direction were detected. At this time, in each device, a shielding plate was installed or the light receiving means was installed at an inclination angle of several degrees from the optical axis of the laser beam so that the laser beam that passed directly through the light receiving means did not enter the light receiving means.

[Problems to be Solved by the Invention] In the above-mentioned prior art, in the photometric device, the photometric positioning means makes a determination based on the integrated output of the spectrometer that performs temperature sampling in synchronization with the low movement of the sample cell.

The fact that the sample must move at the same time as the sample cell did not take temperature into consideration, and there was a problem with its applicability to samples in fluids.

In addition, since the above-mentioned positioning means is accompanied by mechanical vibration,
No consideration was given to the fact that there are limits to the speed of one movement and the distance traveled, and there was a problem in that it took a long time to accurately detect the sample position over a wide area.

Furthermore, no consideration has been given to the fact that for a sample to pass through a light beam with a finite width, it takes time equal to the width of the light beam divided by the moving speed of the sample. However, there was a problem in that the positional resolution was limited.

On the other hand, flow cytometers and optical particle detection devices
- Since this is a device for detecting the number of samples passing through a point and their properties, it does not take into consideration the detection method that detects changes in one position, and samples in a flux that can swim with a certain width are not considered. There was a problem in that it was not suitable for position detection.

The object of the invention is to do so without using mechanical means.

The object of the present invention is to solve the above-mentioned problems of the prior art by providing a technique for detecting the particle level i1 in a fluid with high accuracy.

[Failure to solve the problem]

The above-mentioned problem is achieved by installing a means for converting light from a light source into parallel light beams, and a light receiving section consisting of a lens and a one-dimensional or two-dimensional picture element placed at the image position of the sample.

This is achieved by detecting the scattering position of the parallel light rays scattered by the sample using a light receiving section consisting of a lens and a surface recognition element placed at the very position of the lens.

Here, the scattering intensity distribution of parallel light rays scattered by the sample is expected to be monoisotropic or forward scattering is the strongest, so the optical axis of the light receiving section is set on the extension of the optical path from the light source to the sample surface. It is effective to do so.

At the same time, in order to prevent the scattered light from the sample from being interfered with by the direct light from the light source that has passed through the lens, a shielding plate is installed at the focal point of the lens to prevent the M incidental light component from entering the image @ element. . At this time, the shielding plate is made sufficiently small in order to suppress a decrease in the intensity of the scattered light.

[Operation] Parallel light beams projected onto the sample surface are scattered by the sample having a VC distribution at any position within the plane intersected by the parallel light beams on the sample surface. At this time, the scattered parallel light beams reflect the passing position of the sample, the concentration of the sample, and the food of the sample.

The shape and number of pharyngeals create different scattering positions and scattering intensities. In addition, since the light scattered at the position where the sample passed is focused by the light receiving lens and formed into an image at the corresponding position on the image element, all data on the light receiving position and light receiving intensity on the 11!11 element are processed. By performing comparison calculations in the circuit 1cE, the passing position of the sample and the concentration of the sample can be detected.

Here, the optical axis of the light receiving section consisting of a lens and one-dimensional or two-dimensional image gratings is set on the extension of the optical path from the light source to the sample surface, and a minute shielding plate is set at the focal point of the lens. By cutting off the parallel light t':iX transmitted from the light source through the sample surface, only the cutting-scattered light from the sample is detected. As a result, the scattered light from the sample that reaches the 5-pixel gR element is
Compared to the intensity when the light is placed in other directions, the intensity is the same or higher.

Furthermore, since the shielding plate prevents direct light from entering the image gR element, there is no charge seepage from the pixel into which the direct light is incident, and the light-receiving sensitivity can be improved.

〔Example〕

An embodiment of the present invention will be described below with reference to one drawing.

In FIG. 1, a laser oscillator 1 and a cylindrical lens 2 located on its optical axis are shown. A condensing lens 6 and a one-dimensional image element 9 are placed on the optical axis of a light source consisting of a cylindrical lens 3, sandwiching a sample surface 4 therebetween. At this time, a shield 5 is installed adjacent to the condensing lens 6, and at the same time, a minute shielding plate 7 supported by a shielding plate support part 8 made of a light-transmitting material is placed at the focal point of the condensing lens 6 = VC. It is installed so that fine words can be adjusted around the five focal points.

In Fig. 1, the laser beam 11 emitted from the laser oscillator 1 hits the cylindrical lens 2, becomes a fan-shaped laser beam 12, and spreads out, and at the position where it has spread to a sufficient width, the laser beam 11 reaches the cylindrical lens 5VC. Becomes parallel rays. The parallel laser beam 16 thus obtained intersects the sample surface 4 at the scattering position [21]. At this time, the parallel laser light chamber 16, which has entered a position where there is no sample, reaches the aperture 5 and the condenser lens 6 while maintaining its parallel state. In the condensing lens 6, the parallel laser beam 16 turns into a condensed laser beam 14 directed toward the focal position, reaches the shielding plate 7, and ends the optical path. - A part of the parallel V laser IQ boat 15 that is incident on the position of sample A, sample B, etc. flowing within the surface of the sample surface 4 is scattered by each sample, so sample A Scattered light from 201. Sample B scattering light 20
2. . . . Then, the light is squeezed by the aperture 5 and condensed by the condensing lens 6, resulting in image #! It reaches element 9.

FIG. 2 shows the optical path of the scattered light 201 when the sample A passes through the point where the original axis of the light receiving section and the sample surface 4 intersect, and the optical paths of the flat parallel laser beam 13 and the condensed laser beam 14, Squeeze 5. A condenser lens 6, a shielding plate 7 supported by a shielding plate support part 8&'c made of a light-transmitting material, and an image yR.
A cross-sectional view showing the relationship of elements 9 is shown. At this time, the scattered light scattered in small angle directions around the optical axis and the unscattered portion are condensed by the condenser lens 6, blocked by the shielding plate 7, and complete the optical path. Therefore, the shadow area 301
The scattered light incident in the direction of the image element 91' cannot reach the image element 91'. Therefore, the shielding plate 7 must be made as small as possible. Also, if the parallel laser beams 13 are completely parallel, the condensing light cannot reach the image element 91'. The laser beam [14] should become infinitely small at the focal point of the condensing lens. Therefore, the shadow area 501 can be made smaller by making the shielding plate the minimum size that is allowable in terms of installation error and processing accuracy. Such a shadow region 501 occurs only in the vicinity of the position where the original scattering by the sample intersects the original axis of the light receiving part in the scattering position 21.

Here, since the valley scattered light scattered by each sample has a scattering pattern depending on the concentration distribution and characteristics of each sample,
The scattered light collected by the condenser lens 6 exhibits an intensity distribution depending on the type and concentration distribution of the sample. Fifth
Figure #C shows the intensity distribution in the image@element due to differences in sample type and concentration distribution.

In FIG. 6, the efficiency curve 401 shows the scattering position 21 caused by the aperture 5° condenser lens 6 and shielding plate 7, and the sample.
This shows the light receiving efficiency that changes depending on the relative relationship with the original scattering occurrence position above. In addition, the received light intensity distribution 501i4. An image obtained by concentrating the center position of the sample on the sample surface with a condensing lens is distributed centered at position 1tao on the element. Calculate the received light intensity at position d0 on the image element at this time. When the sheets are closed, the distance from the position d0 on the image element where the received light intensity becomes 10/ is defined as the half width W0. Each of these parameters is
It has the following relationship with the characteristics of the sample.

Center position I of the do-engineered sample (Ice (scattered intensity per sample) x (center concentration of sample) Wo- (concentration distribution of sample) Since the type of sample injected is known in advance, the temperature can be determined.Therefore, by measuring the above parameters d., d., and vr, the concentration distribution of the sample and the position of the sample can be determined. At this time, sample surface 4
The received light intensity distributions 502 and 505 show the intensity distributions on the image element when the density distributions on the image elements are different.

If there is another sample at the top, the scattered light from the sample is
Reflected on the received light intensity distribution. At this time, the received light intensity distribution 504 due to the scattered light of other samples has its center at a different position from the received light intensity distribution 501, and the received light intensity distribution 5011C270 is calculated. At this time, the overlap of the received light intensity distributions is equal to the overlap of the sample concentration distributions. In this case, the data processing unit performs signal processing to improve the accuracy of each sample. +dO
e "O#...Can be used all over the United States.

Furthermore, even if the sample is distributed in a direction perpendicular to the sample surface, by making the radius of the tie 5 sufficiently small,
Scattered light 201. Scattered light 202. ... has a deep depth of focus (
Become. This [Received light intensity distribution 501, 502, 503, 504 by @ of the sample on the F image element. ···teeth.

The widening of the moat due to focal mismatch is eliminated, and the width distribution of the sample in the width direction on the sample surface 4 can be accurately reflected in the received light intensity distribution.

From the above, the center position of the sample flowing on the sample surface, the center concentration of the sample, and the concentration distribution of the sample can be estimated with higher accuracy using the information such as "Os"On"Oe...".

According to this embodiment, by providing a VcB shielding plate device near the focal point of the light receiving lens, it is possible to reduce interference with scattered light caused by direct light from the light source, and the effect is that weak scattered light can be measured with high precision. There is. Furthermore, by installing the aperture in front of the light receiving lens, there is no spread of the image due to mismatch in focus, which has the effect of improving measurement accuracy. Further, since the position and concentration distribution of the sample flowing on the sample surface are determined by performing signal processing on the distribution of received light intensity on the five image elements, there is an effect of increasing the efficiency of data processing.

Next, Example t is shown in FIG. 4 in which the sample surface is scanned by a parallel beam of light that irradiates the entire limited area on the sample surface.

The configuration shown in FIG. 4 is the cylindrical lens 2. in the configuration shown in FIG. The combination of 50 cylindrical lenses is replaced with two scanners.

At this time, the next scanning laser beam 12 is emitted from the two scanners.
A is the scattering position on the sample surface! 21.

Of these, the scanning laser incident on the position where there is no sample -/l
, line 12A reaches the position of the iris 5. here.

The scanning laser beam 12A incident on the iris hole position is
The condensing laser beam 14AK reaches the condensing lens 6 and heads toward the focal position, and the condensed laser beam 14AK reaches the shielding plate 7Vc, completing the optical path. On the other hand, sample beams flowing within the plane of sample surface 4, sample B, ・
The scanning laser beam #12A incident on the tvC has a scattered light 201, a scattered light 2o2, .
. . , the light is squeezed by the squeezer 5vc and focused onto the image @element 9 by the condensing lens 6.

According to this embodiment, in addition to the embodiment shown in FIG. 1, it is possible to increase the density of parallel rays on the sample surface, so that it can be applied even to samples with a smaller scattering probability. be.

In addition, in FIGS. 1 and 4, the description is focused on detecting the one-dimensional position of the sample.

In these embodiments, the cylindrical lens 2 and the cylindrical lens 5y in FIG. 2 above 4
Dimensional sample distribution can be detected. The same thing is shown in Figure 4.

This can be achieved by making the scanning area of the two scanners a two-dimensional area on the sample surface and replacing one image element 9 with a two-dimensional image element 9'.

According to this embodiment, in addition to the above-mentioned effects, the distribution of the sample can be detected in a two-dimensional manner, and by performing signal processing over time, the entire motion of the sample can be analyzed in a two-dimensional manner. It has the effect of being able to

9. General lamps, light emitting diodes, etc. can be used as light sources, but by using a laser oscillator as one light source, the optical mechanism for obtaining parallel light beams is simplified, and the same intensity of light beams can be obtained. The power required to obtain this is reduced. Furthermore, the parallel light beam obtained by a gas laser or semiconductor laser and a lens or cylindrical lens is monochromatic light.

Since there is no need to consider chromatic aberration in the lens of the light receiving section, the mechanism of the light receiving section is simplified and the weight of the entire light receiving section is reduced.

Of course, in the above embodiment 2 the light source was a laser oscillator, but 1 a normal lamp, a light emitting diode, etc.
It may also be a means for generating arbitrary parallel light rays.

〔Effect of the invention〕

According to the present invention, since the entire width of the sample surface can be scanned only by electrical scanning without mechanical vibration, there is an effect that high-speed processing can be performed.

(9) Since the scattered light is detected by the image element or the image pickup tube, there is an effect that the resolution of sample detection can be improved up to the resolution of the image element or the image pickup tube.

Furthermore, since the scattered light is imaged on the image element using parallel light beams and a combination of a condensing lens and a shielding plate, the received light intensity distribution becomes clear, and this received light intensity distribution can be measured accurately. . Therefore, the center position of the sample and the concentration distribution of the sample can be processed with simple calculations, which has the effect of speeding up data processing.

[Brief explanation of the drawing]

FIG. 1 shows a light source of an optical detection device according to an embodiment of the present invention;
Fig. 2 is a cross-sectional view showing the relationship between scattered light and direct light from the sample of the apparatus shown in Fig. 1; is a diagram showing the intensity of light received on the pixel m element by several types of samples with a certain degree of concentration distribution, IF5, and Figure 4 is an overview diagram of the device in Figure 1 when the light source is replaced with a scanning parallel beam. show. 1... Laser oscillator 2.3... Cylindrical lens. 4...Sample surface, 5...Squeezing. 6... Condenser lens, 7... Shielding plate. 9.9'... Image element 5 A, B, O... Sample A, B, 0°501.5
02,505,504...Received light intensity distribution. Two people...Suchu Yana. Wataru Elephant A

Claims (1)

[Claims] 1. In an optical detection device consisting of a sample surface on which the sample moves, a light source that projects light onto the sample surface, a lens that focuses the light that has passed through the sample surface, and a data processing circuit. An optical detection device comprising: means for converting the light from the light source into parallel light beams; and a light receiving section comprising a one-dimensional or two-dimensional image element installed at the position of the lens and the image of the sample. 2. In claim 1, in order to detect forward scattered light from a sample located at an arbitrary position on the sample surface, the lens and image element are installed on an extension line on the optical axis of the optical path from the light source to the sample surface. An optical detection device characterized by: 3. The optical detection device according to claim 1 or 2, characterized in that a shielding plate is installed at a focal point position on the optical axis of the lens so that direct light from the light source transmitted through the lens does not enter the image element. 4. Claim 14 is characterized in that the parallel light beam has a width that illuminates one point or a finite area on the sample surface, and by scanning the sample surface with the parallel light beam, a necessary area on the sample surface is irradiated. Optical detection device. 5. The optical detection device according to claim 1, characterized in that the parallel light beam has a width that can illuminate a sufficiently wide area of the sample surface, and the parallel light beam illuminates a necessary area on the sample surface without scanning the sample surface. .