JP2855073B2 - Paper fiber orientation measuring method and fiber orientation measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber orientation measuring method and a fiber orientation measuring apparatus suitable for measuring the fiber orientation characteristics of paper in a papermaking process.

[0002]

2. Description of the Related Art In order to produce high quality paper, it is necessary to measure the paper quality and fiber orientation characteristics of the produced paper. A conventional fiber orientation measuring apparatus of this type is disclosed in JP-A-4-57.
No. 983, a non-contact type orientation meter,
There is a fiber orientation measuring device described in JP-A-113205, etc., and these devices make use of the incidence and reflection of light on paper.

[0003] Although these conventional devices are suitable for measuring the fiber orientation characteristics of the cut sample, there is an inconvenience in measuring the fiber orientation characteristics of the web in the paper making process. For this reason, the present applicant has already proposed a fiber orientation measuring method and a fiber orientation measuring apparatus capable of measuring the fiber orientation characteristics of a web in a paper making process online (Japanese Patent Application No. 5-62581).
issue).

In this method for measuring the fiber orientation of paper, non-polarized light is radiated perpendicularly to the paper surface of a stationary or running paper, and light is incident on a surface parallel to the paper surface on the non-polarized light incident side of the paper surface. At eight or more locations on the circumference in the parallel plane centered on the intersection with the optical axis, the light reflected by the paper surface is captured almost simultaneously, and the fiber orientation index, fiber orientation angle, etc. are obtained from the intensity of the reflected light. Is characterized by calculating the fiber orientation characteristics of, the fiber orientation measuring device that has realized this method, the projection means for irradiating non-polarized light perpendicular to the paper surface of the stationary or running paper, The non-polarized light incident side is disposed on the circumference in the parallel plane centered on the intersection of the plane parallel to the plane of the paper and the incident optical axis, and the light receiving unit is disposed between the plane of the paper and the incident optical axis. Eight or more light receiving means for capturing light reflected by the paper surface facing the intersection, An optical information processing circuit for receiving the reflected light intensity measured by each light receiving means, appropriately processing the input signal and outputting light intensity information, and a fiber orientation index from the output signal of the optical information processing circuit. And an arithmetic circuit for calculating a fiber orientation angle and the like.

[0005] In general, when measuring the light intensity of the reflected light for paper produced in a paper machine, such as a fourdrinier 6
Is represented as a periodic function of the period π. This can also be confirmed by the above-described fiber orientation measuring device proposed earlier by the present applicant. That is, since the fiber orientation characteristics of the web are related to the light intensity, the fiber orientation characteristics of the web can be substantially determined from the result obtained by measuring the period.

However, the above-described conventional fiber orientation measuring apparatus requires eight or more light receiving means to capture light from the paper at eight or more locations on the circumference. Therefore, the calculation of the fiber orientation index and the fiber orientation angle for evaluating the fiber orientation characteristics is performed for each of these eight locations. In order to perform online measurement and feed back the measurement result to a wire part of a paper machine or the like, a shorter calculation time can be promptly reflected in paper quality.

Therefore, the present invention can reduce the number of parts by reducing the number of measurement positions, thereby reducing the weight and size, and shortening the calculation time to quickly reflect the measurement results, thereby improving the performance. It is an object of the present invention to provide a paper fiber orientation measuring method and a fiber orientation measuring device that contribute to the production of quality paper.

[0008]

As a technical means for achieving the above-mentioned object, a method for measuring the fiber orientation of paper according to the present invention provides a method for unpolarized light perpendicular to the paper surface of a stationary or running paper. Irradiating, at least four locations on a semicircular arc in the parallel plane centered on the intersection of the plane of incidence and the plane of incidence of the unpolarized light on the plane of the paper and the plane of the paper, At any of these four positions, the light reflected by the paper surface is captured almost simultaneously at a position where the positional relationship is not 180 °, and the intensity distribution of the reflected light is approximated by a curve so that the light is reflected on the paper.
Orientation to contribute to the evaluation of fiber orientation characteristics
The main feature is to seek .

Then, in order to carry out the above-mentioned measuring method on a paper machine, non-polarized light is irradiated perpendicularly to the paper surface of the paper running on the paper machine, and the light is incident on the non-polarized light incident side of the paper surface. And at least four positions on a semicircular arc in the parallel plane centered on the intersection of the plane parallel to the paper surface and the incident optical axis, and none of these four places has a 180 ° positional relationship. At approximately the same time, the light reflected by the paper surface is captured, the unpolarized irradiation position is scanned in the cross machine direction of the paper machine, and the intensity distribution of the reflected light is approximated by a curve.
To contribute to the evaluation of the fiber orientation characteristics of the paper.
The fiber orientation angle is determined .

[0010] Further, regarding the fiber orientation characteristics of paper at rest or running on a paper machine, in order to measure the difference between the front and back sides of a paper web, unpolarized light is perpendicular to each of the felt surface and the wire surface of the paper. It is characterized by irradiating and capturing the reflected light on each side.

Further, the intensity of the reflected light to be measured is such that the light itself reflected by the paper surface can be selected so that a desired specification can be selected from the relationship between the required measurement accuracy and the number of parts and the cost of parts.
It is characterized in that, of the light reflected by the paper surface, it is related to either polarized light oscillating in a direction parallel to a plane including the incident optical axis and the reflected optical axis, or polarized light oscillating in the vertical direction.

Further, in order to perform a more accurate measurement, the light reflected by the paper surface is captured on the semicircular arc centered on the intersection of the plane parallel to the paper surface and the incident optical axis. Therefore, when the semicircle is divided into N equal parts, the operation is performed at N places.

The fiber orientation measuring apparatus suitable for carrying out the paper fiber orientation measuring method according to the present invention includes:
A light projecting unit that irradiates non-polarized light perpendicularly to the paper surface of the stationary or running paper, and the center of the intersection of the plane parallel to the paper surface and the incident optical axis on the non-polarized light incident side of the paper surface. Are arranged on a semicircular arc in the parallel plane in a state where none of them are in a 180 ° positional relationship, and light reflected by the paper surface at a light receiving unit facing an intersection between the paper surface and an incident optical axis. At least four light receiving means for capturing light, a reflected light intensity measured by each of the light receiving means, an optical information processing circuit for appropriately processing the input signal and outputting light intensity information, From the output signal of the information processing circuit ,
Approximate the curve to evaluate the fiber orientation characteristics of the paper.
And an arithmetic circuit for calculating a fiber orientation angle to be applied.

[0014] As an apparatus suitable for mounting this apparatus on a paper machine, a light projecting means for irradiating non-polarized light perpendicularly to the paper surface of a paper running on the paper machine, None of them are arranged in a state where there is no 180 ° positional relationship on a semicircular arc in the parallel plane centered on the intersection of the plane of incidence and the plane parallel to the plane of the drawing on the polarization incident side. A light receiving unit facing at the intersection of the paper surface and the incident optical axis to capture light reflected by the paper surface, at least four light receiving units, and reflected light intensities measured by the respective light receiving units are input; An optical information processing circuit that appropriately processes an input signal and outputs light intensity information, and an output signal of the optical information processing circuit.
The distribution of the intensity of the reflected light is approximated by a curve, and the fiber
Calculate fiber orientation angle to contribute to evaluation of fiber orientation characteristics
The light emitting means and the light receiving means are scanned in the cross machine direction of the paper machine.

[0015] Further, regarding the fiber orientation characteristics of paper that is stationary or running on a paper machine, an apparatus suitable for measuring the difference between the front and back sides of a paper web is provided, and the paper surface is a felt surface and a wire surface. And light receiving means for capturing the reflected light on each side.

The light receiving means is not provided with a polarizer, and the incident light axis and the reflected light are reflected from the reflected light so that desired specifications can be selected from the relationship between the required measurement accuracy and the number of parts and the cost of the parts. A polarizer is provided that separates polarized light that oscillates in either the parallel direction or the vertical direction with respect to the plane including the axis.

In order to provide an apparatus for performing more accurate measurement, when M light receiving means are provided, the semicircle centered on the intersection of the plane parallel to the plane of the paper and the incident optical axis is defined as M
It is characterized by being equally divided.

Furthermore, in order to reduce the number of parts to be arranged facing the paper machine and reduce the size and weight so as to be suitable for the case where the paper web on the paper machine is measured, Either one or both of a light projecting unit that irradiates polarized light and a light receiving unit that captures light reflected by the paper surface is configured by an end of an optical fiber. And means connected by the optical fiber. When an optical fiber is used as the light receiving means, the length of the optical fiber is made substantially equal for each light receiving means, so that the reflected light transmitted through the optical fiber is captured almost simultaneously by the light receiving element.

[0019]

The light projecting means irradiates non-polarized light in a direction perpendicular to the plane of the paper, and reflects the reflected light at the center of the intersection of the plane parallel to the paper on the non-polarized light incident side of the paper and the incident optical axis. When the light is captured by a plurality of light receiving means arranged on a semicircular arc in a parallel plane, the angles formed by the incident optical axis and the reflected optical axis are equal for all the light receiving means. Therefore, the variation in the intensity of the reflected light captured by each light receiving means shows a tendency for one cycle according to the orientation characteristics of the paper surface. For this reason, orientation characteristics such as a fiber orientation index and a fiber orientation angle are required from the variation in the intensity of the reflected light.

Further, since there is no rotating member in the optical system for measurement, the structure does not become complicated, and
Reflected light can be captured almost simultaneously by multiple light receiving means,
Measurement in the same part of the paper can be performed in a short time. For this reason, while being easy to mount on a paper machine,
Fiber orientation characteristics of a paper web during high-speed running can be measured.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method and apparatus for measuring the fiber orientation of paper according to the present invention will be specifically described below with reference to the illustrated embodiments.

FIG. 2 is a side view schematically showing the fiber orientation measuring apparatus, and is a view taken along the line AA in FIG. 1. The light projecting means 10 is provided above the paper surface 1a of the paper 1 whose fiber orientation characteristics are to be measured. It is arranged. The light projecting means 10 includes a semiconductor laser 11, a lens 12, a polarizer 13, and a quarter-wave plate 14. The laser beam emitted by the semiconductor laser 11 is transmitted to the lens 12, the polarizer 13, 1/4 The light is transmitted through the wave plate 14 so that circularly polarized light Li can be obtained. Circularly polarized light is light that travels while rotating its polarization direction, and is different from non-polarized light that has no polarization characteristics.However, it is considered as non-polarized light because the rotation period of the polarization direction is extremely short, about ^10-15 seconds. Can be. Of course, a light projecting unit including a halogen lamp that emits non-polarized light and a lens system that converts non-polarized light into parallel light may be used.
The light projecting means 10 is arranged at a position where the circularly polarized light Li is irradiated onto the paper surface 1a in a vertical direction.

On the other hand, the light receiving means 20 comprises a polarizer 21 and a light receiving element 22 for converting the intensity of light into an electric signal. In this embodiment, the light receiving means 20 comprises four light receiving means 20a to 20d. Are provided with polarizers 21a to 21d and light receiving elements 22a to 22d. As shown in FIGS. 1 and 2, these light receiving means 20 have a semicircular shape formed in a plane parallel to the plane of paper 1a and formed at the intersection of the incident optical axis of the circularly polarized light Li and the center. Arranged on an arc. As shown in FIG. 1, the light receiving means 20 is arranged in such a state that the above-mentioned semicircle is divided into approximately four equal parts, and none of them is arranged in a 180 ° positional relationship. . Moreover, these light receiving means 20a to 20d
Are arranged such that the light receiving portion faces the intersection of the incident optical axis of the circularly polarized light Li and the paper surface 1a. Therefore, the laser light emitted from the light projecting means 10 is reflected by the paper surface 1a, and the reflected light Lr is captured by the light receiving means 20a to 20d.

In this embodiment, a configuration having four light receiving means 20 has been described. However, four or more light receiving means 20 may be provided. By providing at least four light receiving means 20, the fiber orientation can be measured with almost satisfactory accuracy in actual measurement. However, since the measurement accuracy can be improved by increasing the number of the light receiving means 20, the light receiving means can be improved in accordance with the quality required for the paper to be manufactured.
You can increase or decrease the number of 20 installations. Further, in the present embodiment, four light receiving means 20 are provided, so that the light receiving means 20 are arranged at positions where the semicircle is divided into four equal parts. However, when four or more, for example, M light receiving means 20 are provided, Is installed at a position where the semicircle is divided into M equal parts.

The reflected light Lr captured by the light receiving means 20a to 20d passes through the polarizers 21a to 21d, is separated into predetermined polarized light, and then enters the light receiving elements 22a to 22d. At this time, the incident and reflected light angle θr formed by the circularly polarized light Li and the reflected light Lr is in the range of 0 ° <θr <90 °,
In order to calculate the fiber orientation, it is desirable that the reflectivity of the light reflecting the fiber orientation is high.
Is desirably increased, and is desirably 50 ° or more, more desirably 70 ° or more. However, the incident / reflection angle θr may be 50 ° or less depending on the paper quality.

When the light receiving means 20a to 20d are locally densely arranged on the arc of the semicircle, data in a deviated direction of the paper surface 1a will be collected, and accurate fiber orientation will be obtained. Characteristics cannot be obtained. Therefore, as described above, it is desirable that the light receiving means 20a to 20d be arranged at positions where the semicircular arc is divided into approximately four equal parts. In the case where the fiber orientation of the paper web can be estimated to be substantially in a certain direction such as the machine direction of the paper web, as in the case of measuring the orientation characteristics of the paper web on the paper machine, the reflected light The light receiving means 20 may be arranged in a position where Lr is easily captured.

For example, when the light receiving means 20a and the light receiving means 20d have a positional relationship of 180 °, measurement is performed at a position shifted by one cycle, so that measurement data can be obtained in the same direction. Then, useless data will be collected. Therefore, each light receiving means 20
Install so that there is no 180 ° positional relationship. That is, in the embodiment shown in FIG. 1, each of the light receiving units 20a to 20d determines
The light intensity at a position 180 ° shifted from 20a to 20d will be sampled. Further, if the measuring position of the light receiving means 20a in this embodiment is 0 °, the light receiving means 20b to 20d are 45 °, 90 °, and 135 ° respectively, and in FIG. 5, these light receiving means 20a to 20d are respectively , A ₀ , b ₀ , c ₀ ,
will be collecting data d _0, be shifted these data one cycle, it is possible to obtain data of a _1, b _1, c _1, d _1.

Further, the polarizer 21 of the light receiving means 20a to 20d
a to 21d denote the incident light axis Li and the reflected light axis Lr from the reflected light Lr.
Or separates the polarized light oscillating in the direction perpendicular to the plane containing
r, and separates polarized light that oscillates in a direction parallel to the plane containing the r. Therefore, the disposed polarizer 21a
In the light receiving elements 22a to 22d, only the polarized light oscillating in the vertical direction or the polarized light oscillating in the parallel direction is captured by the light receiving elements 22a to 22d. The reflected light Lr may be captured by the light receiving elements 22a to 22d without using the polarizers 21a to 21d and separating the polarized light. However, since the highest reflectance of light reflecting the fiber orientation is the polarized light that oscillates in a direction perpendicular to the plane including the incident optical axis Li and the reflected optical axis Lr, the polarized light that separates the polarized light is used. If the intensity of the reflected light Lr is measured using the sub-elements 21a to 21d, the deviation between the collected data becomes large, which is simple and preferable in performing data processing.

Then, as shown in FIG. 3, the light receiving element 22a
Are output terminals of the optical information processing circuit 31.
The intensity of the reflected light Lr captured by the light receiving elements 22a to 22d is converted into an electric signal and input to the optical information processing circuit 31. The optical information processing circuit 31 appropriately processes the input light intensity signal to process the intensity F of the reflected light Lr captured by each of the light receiving elements 22a to 22d and the incident light of the light receiving elements 22a to 22d. It is output as an optical information signal including the arrangement angle θ on the circumference around the axis Li. An arithmetic circuit 32 is connected to the output side of the optical information processing circuit 31, and the arithmetic circuit 32 converts the input optical information signal into

By applying to F (θ) = C (1 + ηCOS2 (θ−α)), an orientation index η representing the strength of the fiber orientation on the paper 1a and an orientation angle α representing the direction of the fiber orientation on the paper 1a. Is calculated. In Equation 1, F represents light intensity, and θ represents light receiving means.
Arrangement angles of 20a to 20d, and C represents the average value of the reflected light intensity. Equation 1 is a part of the Fourier series, and is known as a periodic function that approximates the fiber orientation of paper from the acquired data.
A Von Mises function, an elliptic function, or the like can also be used.

The orientation index η and the orientation angle α calculated by the arithmetic circuit 32 are displayed on display means 33 such as a CRT display connected to the arithmetic circuit 32,
It is printed by a printer or plotter connected to 32.

A sample (paper) cut into one oval using the paper fiber orientation measuring apparatus constructed as described above.
When measuring the orientation characteristics of the sample, the sample stage with the fixed sample is moved in a predetermined direction with this device fixed, or the data is collected while moving the device with the sample stage fixed. Once obtained, the two-dimensional fiber orientation distribution of the sample can be measured. In addition, if the measurement is performed on the front and back of the sample, the fiber orientation distribution on the wire surface and the felt surface of the sample can be measured, and the fiber orientation distribution on the front and back of the sample can be measured.

When measuring the fiber orientation characteristics of the paper web during the papermaking process, a support is provided on both sides in the width direction of the paper machine, and a guide rail is extended over the support, and the fiber orientation measuring device is used. What is necessary is just to install it on a paper machine, being guided by a guide rail so as to be movable. And
By scanning the fiber orientation measuring device in the cross machine direction along the guide rail, the fiber orientation characteristics of the web in the machine direction and the cross machine direction can be measured. Furthermore, if this apparatus is installed on the wire side and the felt side of the paper web during the paper making process and is scanned in the cross machine direction, the front-back difference of the fiber orientation characteristics in the machine direction and the cross machine direction can be measured. . When scanning is not performed, the fiber orientation characteristics of the paper web with respect to the machine direction can be measured.

FIG. 4 shows another embodiment of this apparatus, which is a schematic side view corresponding to FIG. 2, and the same parts as those of the embodiment shown in FIGS. The description is omitted. At the position where the light receiving unit 20 is provided, a polarizer 21 and a reflected light input unit 41 are provided as a light receiving unit. An optical fiber 42 is connected to each of the reflected light input sections 41, and a light receiving element (not shown) is connected to an output side of the optical fiber 42, and light transmitted through the optical fiber 42 is transmitted to the light receiving element. It is designed to be incident. Further, the lengths of the optical fibers 42 are made substantially equal to each other so that the reflected light reflected by the paper surface 1a and captured by the reflected light input section 41 is incident on each light receiving element almost simultaneously.

Therefore, the reflected light reflected on the paper surface 1a passes through the polarizer 21, and becomes polarized light oscillating in a direction perpendicular to or parallel to a plane including the incident optical axis Li and the reflected optical axis Lr. The light is separated and incident on the reflected light incident part 41.
Then, the light passes through the optical fiber 42, is incident on each of the light receiving elements at substantially the same time, is photoelectrically converted, and is input to the optical information processing circuit 31 in the same manner as described above, and the arithmetic circuit 32 calculates the orientation index η and the orientation angle α. Is calculated.

In the embodiment shown in FIG. 5, an optical fiber 42 is connected to a reflected light input section 41, and an output section of the optical fiber 42 is connected to the optical fiber 42.
43 faces the polarizer 21 so that the linearly polarized light transmitted through the polarizer 21 enters the light receiving element 22. FIG. 5 is also a schematic side view corresponding to FIG. 2, and the same parts as those in the embodiment shown in FIGS. In this structure, the polarization characteristic of the light reflected on the paper surface 1a needs to be preserved up to the output unit 43. Therefore, the optical fiber 42 has a single polarization plane preservation mode.

Therefore, the reflected light reflected on the paper surface 1a enters from the reflected light input unit 41 and passes through the optical fiber 42 while maintaining the polarization characteristics. The reflected light emitted from the output unit 43 passes through the polarizer 21 and is separated into polarized light oscillating in a direction perpendicular to or parallel to a plane including the incident optical axis Li and the reflected optical axis Lr. And
The separated polarized light is captured by the light receiving element 22. Then
Photoelectric conversion is performed by the light receiving element 22 and input to the optical information processing circuit 31 in the same manner as described above, and the arithmetic circuit 32 calculates the orientation index η and the orientation angle α.

In the configuration using the optical fiber 42, only the input end of the optical fiber 42 is provided at the portion of the fiber orientation measuring device installed near the paper 1, so that The parts are reduced in size and weight. For this reason, when performing on-line measurement by scanning in the cross-machine direction, it is possible to reduce the space for installing the relevant portion and reduce the power for driving the apparatus in the cross-machine direction.

In these embodiments, the configuration using the optical fiber for the light receiving means 20 has been described.
Alternatively, a configuration using an optical fiber, or a configuration using an optical fiber for both the light projecting means 10 and the light receiving means 20 can be achieved, and the size and weight of the above-described portion can be further reduced.

[0039]

As described above, according to the method and apparatus for measuring the fiber orientation of paper according to the present invention, the incident light is made unpolarized, and the reflected light from the paper surface is almost simultaneously emitted by the plurality of light receiving means. Since the fiber orientation characteristics are measured by capturing, the measurement can be performed in a very short time without requiring a rotating body in the optical system. In addition, since the structure does not require a rotating body, the size can be reduced without a complicated structure. Moreover, the measurement can be performed without contacting the paper and without breaking the paper.

The light receiving means is arranged on a semicircular arc in a plane parallel to the paper to be measured so that measurement can be performed only for one cycle. It is only necessary to install half the number of devices compared to the structure, and the size and weight of the device can be reduced, and the cost can be reduced.

Further, since the measurement time can be extremely short, the fiber orientation characteristics of the paper running at high speed can be easily and almost accurately measured. For this reason, it can be installed on a paper machine to perform online measurement, and if it is installed opposite to the front and back of the paper web on the paper machine, the fiber on the wire side and felt side of the paper web can be easily obtained. Measurement and comparison of orientation characteristics can be performed. Therefore, the measurement result can be quickly fed back to the operation state of the paper machine, and the quality of the manufactured paper can be improved.

In addition, in the off-line measurement, the fiber orientation distribution in a desired direction of one sample can be measured,
If you measure the felt surface and the wire surface of the sample,
The fiber orientation distribution with respect to the front-back difference of the sample can be measured, and these can be greatly used for quality inspection.

[Brief description of the drawings]

FIG. 1 is a plan view showing a schematic structure of a measuring unit of a fiber orientation measuring device according to the present invention.

FIG. 2 is a side view showing a schematic structure of a measuring unit of the paper fiber orientation measuring apparatus according to the present invention, and is a view as viewed in the direction of arrows AA in FIG.

FIG. 3 is a schematic circuit block diagram showing a configuration for arithmetically processing an optical information signal of the fiber orientation measuring apparatus according to the present invention.

FIG. 4 is a view for explaining another embodiment of the fiber orientation measuring apparatus according to the present invention, and is a side view corresponding to FIG. 2;

FIG. 5 is a view for explaining another embodiment of the fiber orientation measuring apparatus according to the present invention, and is a side view corresponding to FIG. 2;

FIG. 6 is a graph for explaining characteristics of light intensity on the surface of a general paper.

[Explanation of symbols]

 1 Paper 1a Paper surface 10 Light emitting means 11 Semiconductor laser 12 Lens 13 Polarizer 14 Quarter wave plate 20a-20d Light receiving means 21a-21d Polarizer 22a-22d Light receiving element 31 Optical information processing circuit 32 Operation circuit 33 Display means 41 Reflection Optical input part 42 Optical fiber 43 Output part Li Incident light Lr Reflected light θr Incident reflected light angle

Continuation of the front page (72) Inventor Akio Hatano 5-21-1, Oji, Kita-ku, Tokyo Nippon Paper Industries Central Research Laboratory (56) References US Patent 3,807,868 (US, A) (58) Fields investigated ( Int.Cl. ⁶ , DB name) D21F 7/06 D21F 7/00 G01B 11/26 G01N 21/47

Claims (11)

(57) [Claims] 1. A non-polarized light is radiated perpendicularly to a paper surface of a stationary or running paper, and a center of the intersection of an incident optical axis and a plane parallel to the paper surface on the non-polarized light incident side of the paper surface. At least four points on a semicircular arc in the parallel plane,
At any of the four positions, the light reflected by the paper surface is captured almost simultaneously at a position where the positional relationship is not 180 °, and the distribution of the intensity of the reflected light is approximated by a curve to obtain a curve.
Calculate fiber orientation angle to contribute to evaluation of fiber orientation characteristics
A method for measuring the fiber orientation of paper. 2. A non-polarized light is irradiated perpendicularly to the paper surface of a paper running on a paper machine, and an intersection point between a plane parallel to the paper surface on the non-polarized light incident side of the paper surface and the incident optical axis is determined. At least four points on a semicircular arc in the parallel plane as a center,
Any of these four places captures light reflected by the paper surface at almost the same time at a position where the positional relationship is not 180 °, scans the unpolarized irradiation position in the cross machine direction of the paper machine, and obtains the intensity of the reflected light. Curve approximation of the distribution of
Fiber orientation angle to contribute to the evaluation of fiber orientation characteristics
Fiber orientation measuring method of paper online and finding. 3. The paper according to claim 1, wherein the felt surface and the wire surface of the paper are irradiated with unpolarized light perpendicularly, and the reflected light is captured on each side. 3. The method for measuring the fiber orientation of paper according to 1. 4. The reflected light intensity to be measured is one of a polarized light oscillating in a direction parallel to a plane including an incident optical axis and a reflected optical axis, or a polarized light oscillating in a vertical direction, of the light reflected by the paper surface. The method according to any one of claims 1 to 3, wherein the fiber orientation of the paper is measured. 5. A method of capturing light reflected by a paper surface on an arc of the semicircle centered on an intersection of a plane parallel to the paper surface and an incident optical axis, and dividing the semicircle into N equal parts. 5. The method for measuring the fiber orientation of paper according to claim 1, wherein the method is performed at N places. 6. A light projecting means for irradiating non-polarized light perpendicularly to a paper surface of a stationary or running paper, and a surface parallel to the paper surface on the non-polarized light incident side of the paper surface and an incident optical axis. Are arranged in a state where none of them are in a 180 ° positional relationship on a semicircular arc in the parallel plane centered at the intersection of the light receiving unit, and the light receiving unit faces the intersection of the paper surface and the incident optical axis. At least four light receiving means for capturing light reflected by the paper surface, and optical information processing for inputting reflected light intensity measured by each of the light receiving means, appropriately processing the input signal, and outputting light intensity information A distribution of intensity of reflected light from an output signal of the optical information processing circuit;
Is approximated by a curve to evaluate the fiber orientation characteristics of the paper.
A paper fiber orientation measuring device, comprising: an arithmetic circuit for calculating a fiber orientation angle for contribution . 7. A light projecting means for irradiating non-polarized light perpendicularly to a paper surface of a paper running on a paper machine, and a plane parallel to the paper surface on the non-polarized light incident side of the paper surface. All are arranged in a state where there is no 180 ° positional relationship on a semicircular arc in the parallel plane centered on the intersection with the axis, and the light receiving unit faces the intersection between the paper surface and the incident optical axis. And at least four light receiving means for capturing the light reflected by the paper surface, and light for receiving the reflected light intensity measured by each of the light receiving means, appropriately processing the input signal, and outputting light intensity information. An information processing circuit; and a distribution of the intensity of reflected light from an output signal of the optical information processing circuit.
Is approximated by a curve to evaluate the fiber orientation characteristics of the paper.
An apparatus for measuring the fiber orientation of paper, comprising: an arithmetic circuit for determining a fiber orientation angle for contribution , wherein the light projecting means and the light receiving means are scanned in a cross machine direction of the paper machine. 8. The apparatus according to claim 1, wherein said paper surface is a felt surface and a wire surface, and said light projecting means for irradiating each surface and said light receiving means for capturing reflected light thereof on each side are provided. The paper fiber orientation measuring device according to claim 6 or 7. 9. The method according to claim 9, wherein the light receiving unit includes a polarizer that separates polarized light that oscillates from the reflected light in a direction parallel or perpendicular to a plane including the incident optical axis and the reflected optical axis. The paper fiber orientation measuring device according to any one of claims 6 to 8, wherein: 10. The apparatus according to claim 6, wherein when M light receiving means are provided, said semicircle centered on an intersection of a plane parallel to said paper surface and an incident optical axis is divided into M equal parts. The paper fiber orientation measuring device according to claim 9. 11. One or both of a light projecting unit that irradiates non-polarized light perpendicular to the paper surface and a light receiving unit that captures light reflected by the paper surface is configured by an end of an optical fiber; 11. The paper fiber orientation measuring device according to claim 6, wherein the light emitting unit and the light emitting unit or the light receiving unit and the light receiving unit are connected by the optical fiber.