JPS5835425A - Liquid crystal polarization meter - Google Patents

Abstract

PURPOSE:To make it possible to measure the phase difference, double refraction quantity, and the like of an anisotropic sample in a simple structure, by attaching a liquid crystal cell which is driven by an electric field. CONSTITUTION:The light transmitted through the sample 3 becomes the elliptically polarized light in general and inputted into the liquid crystal cell 4. The abnormal light refractive index of the liquid crystal cell 4 is varied by the electric field applied to electrodes 12 and 13. Therefore, the light transmitted through the liquid crystal cell becomes the linearly polarized light in the same vibrating direction as that of a polarizer 2 by adjusting the electric field. With the amount of light in an observing system 6 being observed, the electric field to be applied to the liquid crystal cell 4 is adjusted so that the light is not inputted into the observing system. At the same time, the temperature of a crystal 14 is detected by a temperature sensor 18. The phase delay of the liquid crystal 4 and the phase delay or double refraction quantity of the sample 3 can be found from the values of the electric field and the temperature at this time. In this way, the phase difference, double refraction quantity, and the like of the sample can be measured by the simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal polarimeter in which a liquid crystal polarizer is layered so that the polarization value can be changed by an electric field.

Sample phase delay, rotation amount, optical rotation 1! A polarimeter is used to measure the amount of light. The measurement principle of a polarimeter varies, but for example, it uses a material known for double-counterfeiting, or a material that has a glazing effect or a Hockey effect, which causes a phase lag in the opposite direction to the sample. A long time ago, there was a technique that compensated for the material used for this compensation and measured the phase delay inherent to the sample due to the compound amount.
The material used for compensation is a quartz crystal formed into a flat plate or catfish-shaped. - A portion of the stomach is essential and is often unsuitable for automatic measurement.

Also, you can automatically measure Faraday 7 or Pockels Dragon 6! However, there are disadvantages in that the device is expensive and requires high voltage.

The purpose of the present invention is to eliminate the drawbacks of the conventional example described above, and to use a liquid crystal, which has traditionally been considered unsuitable for use in polarimeters etc. due to its high temperature dependence. The purpose is to provide an inexpensive liquid crystal polarimeter that can be used for automatic measurement with high accuracy while correcting the refractive index of the sample.
! In a polarimeter for exposing the amount of jlt, etc., a liquid crystal cell with a temperature in the middle of yφ is inserted in the same optical path as the sample, since the amount of birefringence changes due to the electric field. of,
The timing of this measurement is different from that of the known liquid crystal display based on the electric field and S variation.

The invention will be explained in detail on the basis of illustrated embodiments.

In FIG. 1, a polarizer for linearly polarizing light such as light 1 [IN, light 11111ib, etc.] is immersed in the optical path and has a lamp 11 and a lens system 1b! , sample 3, whose extraordinary ray refractive index changes as the electric field II:W&, for example, from neomatic liquid crystal to Weiwei liquid crystal #4, analyzer 5, eye or photoelectron amplification tube, etc., can be used to observe the light intensity and distribution. Just in case, the required Km
An observation system 6 including a Y-Z image system is arranged. The liquid crystal display Jk4 is IIJIIwtII as shown in Figure 2.
! Transparent plates such as plate glass that do not have k -10%11
12.1g of transparent electrodes are coated on each inner cylinder of the liquid crystal display 12, and a liquid crystal 14 is sandwiched therebetween. In addition, spacers 15 and i4 are provided on the scraps of the liquid crystal 14 to hold the transparent electrode 12.1 in parallel r:*, and the transparent electrode 12.13 is used to change the electric field applied to the liquid crystal 14. It is followed by an AC low voltage drive power supply circuit 17. Further, a temperature sensor f-18 for detecting the temperature of the liquid crystal 14 is disposed within or near the liquid crystal 14.
4 can be read on the display section 19.

Furthermore, the polarizer 2, sample 3, liquid crystal cell 4, and analyzer 5 can be rotated within the bacteria perpendicular to the optical path as necessary.

Light emitted from a light source 1 is linearly polarized by a polarizer 2 and enters a sample 6 having birefringence. The azimuth angle of the sample 3 and the azimuth angle of the linearly polarized light of the incident light must match, and are adjusted so that the angle difference is 45 degrees as the optimum angle, as shown in FIG. The light transmitted through the sample device generally becomes elliptically polarized light and enters the liquid crystal cell 4. The azimuth angle of the liquid crystal cell 4 is the same as that of the sample 6.
The direction in which the liquid crystal cell 4 has a low refractive index is arranged to coincide with the direction in which the refractive index of the liquid crystal cell 4 is low. Liquid crystal cell #4 has electrode 12.
15FCThe extraordinary ray refractive index changes depending on the applied electric field, so by adjusting the electric field, the transmitted light of the liquid crystal cell 4 becomes a polarizer! It becomes linearly polarized light according to the hca theory. Analyzer 5
is placed perpendicular to the polarizer 2, so the observation system 6E
However, if the electric field adjustment does not meet the above conditions, the light will pass through 4 to 1 crystal dragon, so the light will be IIIP!
The light becomes polarized and generates an observation component that passes through the polarizer 5, so that the light is incident on the observation system 6. ζζ″eIm
The amount of birefringence for the electric field of the crystal 14 and iat: and the thickness of the liquid crystal 14 are known. If there is no 44Em field, elliptically polarized light is generally emitted from Yoshoryu #4 and enters the observation system 6: &, While observing the light intensity of the observation system number,
1. To prevent the observation system 4IC light from entering the liquid crystal display, avoid the voltage rise. At the same time, the temperature of the liquid crystal 14 is detected by the display section 19 at 11 degrees and 7 inches. The phase delay of liquid crystal cell #40 can be determined from the electric field and IL variation values of this connection. Phase delay and test of liquid crystal cell 4! Since the absolute value of the phase delay of Is is equal and inverted, it may be difficult to determine the state, but it is important to know the amount of distance or double fold in Test II No. 4 4D41k@. X, rotate the liquid crystal cell 41 and analyzer 5, -
It is also possible to measure the optical rotation of the sample device by reading the rotation angle.

FIG. 4 shows another embodiment, in which a first λ74 wave plate 116 is installed between the polarizer 2 and the sample 6 having the amount of i in FIG.
However, a second λ74 wavelength plate 21 is inserted between the liquid crystal panel 4 and the analyzer 5, respectively.

To work to convert the linearly polarized light of the first λ74 wavelength plate 2I catfish polarizer 2 into circularly polarized light, and to work to convert the circularly polarized light of the second 1/4 II long plate 21a back to the original linearly polarized light. The 174 wavelength plates 20 and 21 are arranged so that their azimuths are perpendicular to each other. No. SII shows a further embodiment of El&, in which an optical miscellaneous lens system 21 is inserted between 4 and 4 in the weight sampler and liquid crystal panel shown in FIG. 1, and an arrangement suitable for the 4Hc polarization function It becomes.

ξThese embodiments are similar to the case of No. 11i, and are capable of measuring the phase delay, amount of birefringence, and optical rotation of the sample device. - The observation system 6, the power supply 181117, and the temperature sensor 18 are subjected to a single calculation process, thereby automating the measurement. The cell has a simple structure of a number, and there is a special point to enable the measurement of the phase difference of anisotropic samples, the double-track case, the optical rotation, and the automatic needle. In addition, by incorporating the Faraday effect into a device, 11
! Since it is possible to change the amount of folding, the electric field can be controlled by Harushima, and even compared to a device that uses the 1c# cost effect, it does not use high-voltage direct current, so it is more financially viable.

[Brief explanation of the drawing]

The drawings show an embodiment of the 41-meter crystal polarimeter according to the present invention. Fig. 1 shows the configuration of the first embodiment, Fig. 2 shows the new am of the liquid crystal cell, and No. 3 ml shows the configuration of the polarized vagina. The explanation garden, Figure 4, and Exhibition Figure 115 are the! and the configuration m"e of the first embodiment. Reference numeral 1 is a light source section, ! is a polarizer, 3 is a sample, 4 is a liquid crystal cell, 6 is an analyzer, 6 is an observation system, 11 is a transparent plate, 12.
1 ink is the cross-electrode, 4th is the liquid crystal, 15.16 is the spacer,
17 is the power supply circuit, 1st is the temperature sensor, 20.21 is 17
4 wavelength plate! ! Patent applicant: Canon Co., Ltd. Kinsha 1411 sgii

Claims (1)

[Scope of Claims] 1. In a polarimeter for fixing the amount of double folding of a sample, etc., a temperature sensor that utilizes the double folding amount by an electric field to apply the same light *rs- as the sample. Liquid crystal polarization is used to measure the polarization of a sample by inserting a liquid crystal polarizer into the middle and comparing it with the temporality of a known liquid crystal, which is based on electric field and temperature. Total. 1 sample and liquid crystal panel and 2 soft J/4 II! A liquid crystal polarimeter according to claim 1, wherein a long plate is inserted into the optical path. The liquid crystal polarimeter according to claim 1, wherein a plurality of liquid crystal polarizers are inserted into the five-light path.