JPH0127380B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for continuously measuring the optical axis direction of a polarizing film, and more specifically, to an apparatus for continuously measuring the optical axis direction of an elongated sample to be measured along its longitudinal direction.

When measuring the optical axis direction of a transparent sample, conventionally, as shown in FIG. 1, a light source 1, two polarizers 3a and 3b arranged so that their optical axes are orthogonal to each other,
A chip-shaped sample to be measured 2 is inserted between the polarizers 3a and 3b of the orthogonal Nicol optical system consisting of the light receiver 4 so that its surface is perpendicular to the axis of the optical system. The method used was to rotate the sample and determine the optical axis of the sample from the relationship between the rotation angle and the transmitted light intensity of the optical system. However, with such conventional devices, for example, in the case of a long and slender sample whose optical axis direction changes at each position along its length, in order to know the optical axis direction at each position, it is necessary to It is necessary to divide the sample into pieces of appropriate size and measure the optical axis direction for each sample piece, resulting in a large amount of labor and time loss.

The present invention eliminates the drawbacks of the above-mentioned prior art, makes it possible to continuously measure the optical axis direction in the longitudinal direction of a long sample, and makes the structure or configuration of the device lightweight and compact. The purpose is to provide measuring equipment.

The present invention will be specifically explained with reference to the drawings. FIG. 2 is a perspective view showing an embodiment of the present invention, with a part of the case cut away.

Light source 1, two polarizers 3 whose optical axes are orthogonal to each other
a, 3b, and the light receiver 4 are arranged in a uniaxial direction to constitute an orthogonal Nicol optical system. The sample to be measured 10 is transported or arranged perpendicularly to the arrangement direction of the optical system. This conveyance means continuously moves the long sample to be measured 10 relative to the optical system. The conveyance means is a motor and a speed reducer 3
0, a transmission belt 32, pulleys 33, 34, a conveyance belt 35, a back up roller 36, a guide rail 37, and a guide roll 38. The sample 10 set in the sample holder 11 to be measured is sequentially moved in the longitudinal direction on the guide rail 37 by this conveying means arranged in a direction perpendicular to the arrangement direction of the orthogonal Nicol optical system.

A reference sample 20 that provides a reference value for the relationship between the transmitted light intensity and the optical axis deviation angle for the sample 10 to be measured is provided perpendicularly on the optical axis C. This reference sample 20 and the sample to be measured 10 have two polarizers 3
The reference sample 20 is between sample 1 and sample 1.
used before or after measurement of sample 1 to be measured.
It is removed from the system during the 0 measurement. The reference sample 20 is set in a reference sample holder 21, and the holder 21 is rotated by external operating means. The external operating means includes a worm 61 that meshes with the reference sample holder 21, a first gear 62 fixed coaxially with the worm 61, a second gear 63, a transmission shaft 64, and an operating knob 6.
5. The holder 21 is rotated by rotating the operating knob 65, which is composed of an angle scale 66 and protrudes outside the case 40.

As described above, in the optical axis measuring device consisting of the orthogonal Nicol optical system, sample transport means, external operation means, etc., if the light from the light source 1 enters, accurate measurements cannot be performed, so it is necessary to prevent the intrusion of external light. There is. In this case, it is conceivable to use the case 40 as a case for the entire device so as to cover the entire device to prevent the above-mentioned external light from entering. However, unlike conventional devices, in order to be able to continuously measure long samples with this device, the conveyance means are arranged perpendicular to the arrangement direction of the Nicol optical system, so it would be extremely heavy to enclose the entire device. However, the transmission shaft 64 of the external operating means becomes long, which is not preferable. Therefore, in the present invention, the case 40 is a light-shielding case that only covers the entire crossed Nicol optical system, and the guide rails 37 and guide rollers 38 at both ends of the conveyance means are exposed outside the case 40. In this case, the long sample 10 to be measured is supplied and discharged so as to pass through the case 40. Therefore, in the present invention, a light-shielding hood 5 is provided at the entrance and exit of the sample 10 to be measured.
0 and a light shielding screen 5 inside it.
1 and a light shielding roller 52 are provided to prevent outside light from entering.

The measurement work in the optical axis direction using this device will be explained.
First, the holder 11 with the sample to be measured 10 set therein is inserted into the case 40 from one side along the guide rail 37, and is ejected from the other side. In this way, the transmitted light intensity at each position along the longitudinal direction of the sample 10 to be measured is measured. Next, a reference sample 20 cut out from the same lot as the sample 10 to be measured is set in the holder 21, and the transmitted intensity is measured while rotating it around the optical axis C by an external operating means. Transmitted light intensity I
The following relationship holds between and the deviation angle φ of the optical axis of the sample (the deviation angle between the optical axis of the polarizer 3a and the optical axis of the sample).

I∝sin ² (2φ) Since the reference sample 20 is rotated at least 90 degrees, there is always a point where I=0, and the position of this point is the position where the deviation angle φ=0. Therefore, in the reference sample 20, there is a one-to-one correspondence between the deviation angle φ and the intensity I, so by comparing the transmitted light intensity I at each position in the sample to be measured 10 with that of the reference sample 20, it is possible to The deviation angle φ at each position can be determined.

According to the present invention, a reference sample and a sample to be measured are arranged in series between two polarizers, and the data of the sample to be measured can be processed based on the data of the reference sample. Therefore, by using the same material with the same thickness as the sample to be measured as the reference sample, various factors are eliminated and only the optical axis direction can be measured with high precision. In addition, since the sample to be measured guide rail is provided extending outside the case and the sample to be measured is held in a long holder that is displaced along the guide rail, the size of the case that accommodates the orthogonal Nicol optical system is reduced. However, it has become possible to measure a much larger sample at once and continuously. Furthermore, a light-shielding screen and a pair of light-shielding rollers are installed inside the entrance and exit that pass through the case, so that the pair of light-shielding rollers regulates the posture of the sample to be measured on the guide rail while preventing any foreign matter from leaking through the gap between the light-shielding screens. It has the effect of blocking light well and improving the accuracy of measurement data, as well as allowing continuous measurement work to be carried out smoothly and with high efficiency.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the prior art, and FIG. 2 is a partially cutaway perspective view of an embodiment of the present invention. 1... Light source, 3a, 3b... Polarizer, 4... Light receiver, 10... Sample to be measured, 11... Holder, 2
0...Reference sample, 35...Transport belt, 37...
... Guide rail, 38 ... Guide roll, 40 ... Case, 50 ... Light-shielding hood, 51 ... Light-shielding screen, 52 ... Light-shielding roller.

Claims (1)

[Claims] 1 Arrange two polarizers whose optical axes are orthogonal to each other between a light source and a light receiver to configure an orthogonal Nicol optical system,
In an apparatus in which a reference sample, which is rotatable by an external operating means and can be freely added to and subtracted from the optical system, and a sample to be measured are arranged in series between these two polarizers, the orthogonal Nicol optical The system is housed in a light-shielding case, and a sample guide rail is provided that extends to the outside of the case through two opposing side walls of the light-shielding case in a direction perpendicular to the arrangement direction of the optical system. The sample to be measured is held in an elongated holder that slides along the holder, and a light-shielding screen is provided inside the entrance and exit where the elongated holder penetrates the two side walls of the light-shielding case, and the light-shielding screen A continuous optical axis direction measuring device characterized in that a pair of light shielding rollers are provided on both sides of the guide rail inside the optical axis direction.