JPS61142428A - Light collimator - Google Patents

Abstract

PURPOSE:To introduce only the light radiated at the right angle to incident light to a light detecting system, by applying a black matting treatment on the entire surface of metal or non-metal stable to light and heat while has many through holes aligned in one direction. CONSTITUTION:A polarizing plate 4 is turned properly to make an exciting light polarized in the direction (z) to irradiate a sample through a slit 3. Each fluorescent molecule emits fluorescence over all solid angles. But the light incident slantly to the through holes of a light collimator 1 is absorbed by the blackened surface in the hole while being reflected repeatedly without the holes and eventually, only the light incident to the through hole in parallel can be passed thereby enabling the introduction of the light alone radiated in the direction of (x) axis to the light detecting system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical collimator that selectively passes only light traveling in one direction.

[Technical background of the invention and its problems]

Conventionally, when linearly polarized light is irradiated onto fluorescent molecules in a sample cell and the degree of polarization of the emitted fluorescence is measured, measurement is done simply by placing a polarizing optical element just before or between the fluorescence focusing system. Was. However, in order to determine the exact degree of polarization of fluorescence, it is necessary to measure each fluorescent molecule in a direction perpendicular to the excitation light. Contamination occurs,
It is not possible to measure the degree of polarization accurately.

Therefore, a measurement system as shown in Figure 2 was devised. With this, there is little contamination from directions other than the perpendicular direction, and the influence of multiple scattering is also small. However, the measurement system shown in FIG. 2 is not efficient because the amount of incident light is limited by the slit width.

[Purpose of the invention]

The present invention improves the drawbacks of the conventional devices described above, and aims to provide an optical collimator that can guide only light emitted from a sample cell in a direction perpendicular to the incident light to a photodetection system. .

[Summary of the invention]

The optical collimator for achieving the above purpose has the following features.

The overall shape varies depending on the path of the incident light beam to the sample cell and the configuration of the photodetection system, but the material is a metal or nonmetal that is stable to light and heat, and has many through holes aligned in one direction. All surfaces are treated with a black matte finish. Alternatively, a large number of tubes made of the above-mentioned material whose surfaces are treated with a black matte finish are bundled together.

〔Effect of the invention〕

The light incident obliquely into the through hole of the original collimator of the present invention is
As it is repeatedly reflected within the hole, it is absorbed by the black-treated inner surface of the hole, and in the end, only the light incident parallel to one through hole passes through and is detected by the photodetector r#l.

[Embodiments of the invention]

The present invention will be described in detail below with reference to the drawings. 1st
The figure shows an example of measuring fluorescence polarization using the original collimator according to the present invention.

A liquid sample containing fluorescent molecules is contained in cell No. 2. Reference numeral 6 indicates light from a light source that has been separated into wavelengths suitable for exciting fluorescent molecules, and is turned into light rays parallel to the y-axis direction by a lens or mirror. 4 and 7 are film polarizing plates, and 4 allows only light linearly polarized in the X-axis and biaxial directions, and 7 to pass only linearly polarized light in the y-axis and biaxial directions.

The fluorescence that has passed through 7 enters a spectroscope, and only the light with the maximum fluorescence wavelength enters a photodetector, such as a photomultiplier tube. The output is taken out as a voltage or a photon count when a photomultiplier tube is used.

The actual procedure for measuring the degree of fluorescence polarization is shown below.

First, the polarizing plate 4 is appropriately rotated to irradiate the sample with excitation light polarized in two directions through the slit 3. Although each fluorescent component emits fluorescence over the entire solid angle, only the light emitted in the X-axis direction by the optical collimator 1 of the present invention is guided to the photodetection system. The polarizing plate 7 is rotated, and light components polarized in two directions are detected and output V. Next, in order to detect the light component polarized in the y direction, the output when rotated by 90@ is assumed to be H. At this time, the degree of fluorescence polarization P can be determined by the following equation.

If the polarization characteristics of the optical system on the fluorescence detection side pose a problem, a first-order correction is performed. Rotate the polarizing plate 4 appropriately and x@
The sample is irradiated with excitation light polarized in the force direction. Rotate 7 and 2
The output of the light component polarized in the y direction is then rotated by 90 degrees, and the output of the light component polarized in the y direction is given as . Come in,
The degree of fluorescence polarization P is corrected by kl as shown in the following equation.

[Other embodiments of the invention]

It is not limited to sources emitted in a direction perpendicular to the incident light.

It can be used when you want to measure light emitted in a specific direction. Moreover, it is useful not only for measuring fluorescence but also for measuring scattered light. FIG. 3 shows an example for measuring the angular dependence of scattered light.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing a conventional example of a device designed for measuring fluorescence polarization,
FIG. 3 shows an example of an apparatus for measuring the angular dependence of scattered light of a sample. 1... Optical collimator, 2... Sample cell, 3... Incoming slit, 4... Film polarizing plate, 5... Outgoing slit. 6... Incident light, 7... Emitted light, 8... Rotating plate.

Claims (1)

[Claims] An optical collimator is attached to a device that measures the fluorescence emitted in a direction perpendicular to the incident light by injecting light of a specific wavelength into a sample containing a fluorescent substance. An optical collimator characterized in that it has a large number of through holes arranged in one direction, and its entire surface is treated with a black matte finish.