JPS6353402A - Measurement of eccentricity for light transmitting long-sized body - Google Patents

Abstract

PURPOSE:To achieve accurate measurement, by projecting X- and Y-axis side scatting patterns of a light transmitting object to be measured different in the refractive index between the axis center and the circumference thereof on a screen to compute a natural logarithm value pertaining to the scattering patterns. CONSTITUTION:A long-sized body 30 to be measured comprising an optical fiber 31 and a transparent cover layer 32 is irradiated with X- and Y-axis light beams to project scattering patterns on screens 55 and 56 by light transmitted through the fiber 31 and the layer 32 and distances from the center to both ends of the scattering patterns are represented by XL, XR, YL and YR and distance-ratio natural logarithm ln(XR/XL) and ln(YR/YL). Here, information of the scattering patterns captured by optical systems 57 and 58 and an outer diameter value of the layer 32 captured by a measuring section 61 are inputted into a processing system 59. The system 59 into which a known refractive index pertaining to the layer 32 is inputted through a setter 60 performs a computation based on formulas I and II to determine a relative eccentricity between the fiber 31 and the layer 32.

Description

[Detailed Description of the Invention] [Gamma Industrial Application Field] The present invention is a method for measuring the mutual eccentricity between the axial center and the outer circumference of a long body such as a coated optical fiber or a transparent hollow vibrator. Regarding.

f.Prior Art” An optical fiber covered with a transparent 1Q layer and a long hollow vibe made of a transparent body can both be said to be elongated bodies that have light-transmitting properties.

In the case of the above-mentioned coated optical fiber, the optical fiber is attached to a long body (
The elongated body constitutes one core, and the covering layer constitutes the outer peripheral portion of the elongated body.

In the case of the above-mentioned hollow vibe, the hollow part becomes the axial center of the elongated body, and the pipe itself constitutes the outer peripheral part of the elongated body.

Usually, in these elongated bodies, the axial center portion and the outer peripheral portion have different refractive indexes.

By the way, coated optical fiber! When manufacturing A, a method is used in which the optical fiber is passed through a coating die containing a coating material such as droplet resin, the outer periphery of the optical fiber is coated, and the coating layer is hardened. When producing transparent glass vibrators, plastic extrusion molding means, glass vibrator heating stretching means, etc. are adopted.

When forming the coating layer on the outer periphery of the optical fiber in the above, uneven thickness of the coating layer occurs due to eccentricity between the optical fiber axis and the die axis, so the eccentricity between the elongated body and the coating layer immediately after coating is determined. Based on this, feedback control is performed to adjust the position of the coating die, and even when manufacturing transparent pipes, the eccentricity between the shaft center (hollow part) and the outer circumference was measured, and it was found that uneven thickness of the vibrator occurred. A test is being conducted to see if this is the case.

FIG. 4 shows that an eccentricity measuring means is incorporated into the covering means,
This shows an example of manufacturing a coated optical fiber using this method, and the coating means and eccentricity measuring means will be explained below.
I do.

In Fig. 4, the axis of the optical fiber z<16 is the O-axis, and the two wheels perpendicular to the O-axis are the X-axes.

In the case of a Y machine, the coating die 2 placed on the 0 axis is
The adjustment tables 5 and s for X-axis movement and Y-axis movement are equipped with a drive source 3.4 such as a pulse motor, so that the X-axis direction can be adjusted via these adjustment tables 5.6. , fine adjustment can be made in the Y-axis direction.

xi, as means for measuring the eccentricity in the Y-axis direction, a projector 7 having a laser light source, a spectrometer 8 comprising a half mirror;
It is equipped with reflectors 9.10, screens 12.13, etc.

In these cases, the light beam emitted from the projector 7 is transmitted to the spectrometer 8,
The rays in the Y-axis direction from the reflector 9 to the screen 12 and the rays in the X-axis direction from the reflector 10 to the screen 13 are arranged relative to each other so as to reach the screen 12.13 via the reflector 9.10. It is perpendicular to the O-sleeve.

An optical system 14.15 consisting of, for example, a CCD camera is disposed corresponding to the screen 12.13, and information from these optical systems 14.15 is inputted to an arithmetic processing system', 6 consisting of, for example, a microcomputer. It has become.

In FIG. 4, when the optical fiber la running vertically along the O axis passes through the coating die 2, the optical fiber z<
When the coating layer 1b is formed on the outer periphery of the iH and the coated optical fiber lc is irradiated with light beams in the X-axis direction and the Y-axis direction, the coated optical fiber IC is formed on each screen ]2 and I3. A scattering pattern of is projected.

Note that the scattering pattern referred to here is due to light that has passed through both the coating layer 1b and the optical fiber 1a.

12 screens each! For the scattering patterns on 3, the distances from their centers XO, yo to both ends are XR,
When L, Y, Y, the distance ratios XR/XL and YR/YL when there is no coating thickness unevenness are 1/1, respectively.
However, when uneven coating thickness occurs, this equilibrium state is disrupted.

Therefore, each screen 1 via the optical system 14.15
2. By capturing the scattering pattern on I3, inputting the scattering pattern information to the arithmetic processing system 18, and calculating whether or not the above-mentioned distance ratio is balanced, the presence or absence of uneven coating thickness can be determined.

When uneven coating thickness is found due to the imbalance, in order to correct this, a predetermined control signal is sent from the processing system 16 to the drive system of the adjustment table 5.6, and the position of the coating die 2 is changed to: A
Arrange.

Of course, even in the case of a transparent pipe, the eccentricity between the shaft center portion and the outer peripheral portion can be measured by the eccentricity measuring means shown in FIG.

"Problems to be Solved by the Invention" When measuring the eccentricity between the optical fiber, that is, the axial center part, and the coating layer, that is, the outer peripheral part, using the above-mentioned means, the amount of eccentricity is used as a parameter (XR/XL).

If we have the relationship between the sentence H (YR/YL) and the eccentric angle as a database, we can make a correspondence with the measured values.

However, in the case of coated optical fibers, it is obvious that the outer diameter and refractive index of the coating layer are not uniform, so it is not realistic to create a database with a huge amount of data that can accommodate all outer diameters and refractive indices. Not.

The same applies when measuring the eccentricity of a transparent vibrator.

In view of the above-mentioned problems, the present invention aims to provide a method for accurately measuring the eccentricity between the axial center and the outer circumference of a translucent elongated body using simple calculation means. It is something.

Means for Solving Problem T" In order to achieve the intended purpose of the present invention, the shaft center part and the outer part covering the shaft center part have translucency, and the shaft center part and the outer peripheral part The object to be measured is a long body whose refractive indexes are different from each other, and the line segment passing through the axis of the object is the 0 axis, and the two line segments that intersect the 0 axis at almost right angles are the X axis. , and the Y axis, the light irradiation part and the screen of the light irradiation system facing each other with the object to be measured are placed on the X axis and the Y axis, respectively, and the A light beam is irradiated from each light irradiation part to the measured object, and the scattering pattern of the light transmitted through the outer part and the axial center of the measured object is expressed on the X axis and YI.
Each distance from the center to both ends of the scattering pattern projected on the screen on the X axis is defined as X[, XL), and each distance from the center to both ends of the scattering pattern projected on the screen on the Y axis is Yl, , YRl, and the natural logarithm of the distance subratio is n(
Yq/Yt,), each of the above scattering patterns is captured by an optical means, the information of these scattering patterns is manually inputted to a calculation processing system, and the above in(Xx/Xt) is obtained through the calculation processing system. , n(XR/XL)=A-sinθ−−−−−−−(
1) in(YR/YL)--A ・cos O--
- Equation (2) (where A is the amplitude of the above trigonometric function, the state quantity determined by the outer diameter of the outer circumference, the refractive index, and the amount of eccentricity, 0 is the eccentricity angle of the object to be measured, and the Jllll constant of the object to be measured is The angle formed by the reference line passing through the center of the object's outer shape and the line segment passing through the center of the object's outer shape and the center of the axis. It is characterized by calculating the eccentricity ratio by performing arithmetic processing.

"Example" Below, -4.: A specific example of the invention method will be described with reference to one drawing.

Figure 1 shows the number 1! This is an example of the + side deviation when the elongated body 3G, which is a constant object, is made of a coated optical fiber.

As is well known, the elongated body 30 in this case has its axial center 31
is a transparent optical fiber made of quartz or plastic, and its outer peripheral portion 32 is also made of a transparent coating layer made of plastic.

In FIG. 1, the axial center line of the axial center portion (optical fiber) 31 is defined as the O axis, and is approximately perpendicular to the O axis, for example, at an angle of 85°.
If two axes that intersect at an angle of ~95° are defined as the X axis and the Y axis, the coating die 40 located on the 0 axis is a die for moving in the X axis direction equipped with a drive source 41, 42 such as a pulse motor. , and on adjustment tables 43 and 44 for movement in the Y-axis direction, fine movement adjustment can be made in the X-axis direction and the Y-axis direction via these adjustment tables 43 and 44.

A light irradiation system 50 that serves both the X-axis direction and the Y-axis direction includes a light projector 51. Spectrometer 52 consisting of a half mirror, reflection f! It is equipped with 53.54.

The eccentricity measuring means in the X-axis direction and the Y-axis direction is configured via the light irradiation system 50 and the screens 55 and 56.

That is, when the screens 55 and 56 are arranged below the adjustment table 43 and 44 on the X axis and the Y axis as shown in FIG. 1, the light beam L emitted from the projector 51
Each part of the light irradiation system 50 is arranged so that the light beams LX and LY are separated into LX and LY via the spectroscope 52, and these separated light beams LX and LY reach the screen 55.56 via the reflecting mirror 53.54. be done.

In this case, the light beam LX in the X-axis direction extending from the reflector 53 to the screen 55 and the light beam LY in the X-axis direction extending from the reflector 54 to the screen 5B are substantially perpendicular to the ○ axis, X in the light irradiation system 50! It becomes a light irradiation part in the k11 direction and the Y-axis direction.

When the light irradiation systems in the X-axis direction and the Y-axis direction are made independent from each other, the projectors 51 may be placed at predetermined positions on the X-axis and the Y-axis, respectively.

Optical systems 57 and 58 consisting of, for example, a CCD camera are arranged corresponding to the screens 55 and 56, and information from these optical systems 57 and 58 is inputted to an arithmetic processing system 59 consisting of, for example, a microcomputer. ing.

A refractive index setting device 60 for inputting the refractive index regarding the elongated body 30 is connected to the arithmetic processing system 59, and a refractive index setting device 60 for inputting the refractive index regarding the elongated body 30 is connected, as well as an outer diameter setting device for the elongated body disposed directly below the adjustment table 43, 44. A Jllll meter 61 is connected.

In FIG. 1, when an axial center portion (optical fiber) 31 for a long body that runs up and down along an O-suke passes through a coating die 40, an outer peripheral portion (a coating layer) is attached to the outer circumference of the axial center portion 31. )3
2 is formed, and light beams LX, L in the X-axis direction and the Y-axis direction are applied to the elongated body 30 consisting of the axial center portion 31 and the outer peripheral portion 32.
When the elongated body 30 is irradiated with the elongated body 30, a scattering pattern of the elongated body 30 due to the light transmitted through both the outer peripheral portion 32 and the axial center portion 31 is projected onto each screen 55,561-.

The known refractive index regarding the outer circumferential portion 32 is inputted to the arithmetic processing system 58 via the refractive index j'j' + refraction L:' Information on each of the above 1 Garan patterns, outer diameter 5111 regulator 6
The outer diameter of the outer circumferential portion 32 taken through 1 is respectively input.

Thus, the arithmetic processing system 59 to which the predetermined information has been input calculates the relative relationship between the shaft center portion 31 and the outer peripheral portion 32 through arithmetic processing based on equations (1) and (2) (first-order monomials of trigonometric functions). The eccentricity is determined, and if the eccentricity is found, a predetermined control signal is sent from the arithmetic processing system 59 to the drive system of the adjustment table 43, 44, and the position of the coating die 4o is adjusted by 7A.

Next, scattered light generated when a light beam is irradiated toward the elongated body 3o from the biaxial directions will be described.

Generally, the above-mentioned scattered light consists of the following three types, and these three types of scattered light are mixed on each screen 55,561-.

■ Light beams LX and LY are at the axial center (optical fiber) 31
and the outer peripheral part (coating layer) 32 (β;
, β; when <1).

(S) When the light beams L× and LY are reflected at the axial center portion 31 (when β1 1.β; >1).

■ When the light beams LX and LY pass through only the outer peripheral portion 32 (when β;>i).

The scattered light handled in the present invention is the case of (2) above, and the second
If we explain this with reference to the figure, we get the following equation.

θ0=sin-'x θ+=sin-'z(1/nl-5in oo)β1
=1/r-sin θ+-e/r-sin(θ0-θI◆
φ) θ2=sim publication βI βz=n+/n2-sirr 02 θ3=sin-'β2 θ4=04 θ5=02 θ6=s'+n-' (rs:nθ2+e-sin
(θ0−θI+2(θβ03)+φ)]θy=sin
-1(nI-slnθ6)ψ-(θ0-θ+)+2(θ
? -03) + (θjiθ6) In general, the above-mentioned scattered light ■ is a very small amount in terms of the total amount, so it can be ignored. 32) The refractive index of n? In this case, most of the coated optical fibers have nI > β2, and with this refractive index relationship, the scattered light () is widely distributed outside the screen, while the scattered light (quenched) is distributed around the center of the screen. Therefore, the scattered light of ■■ can be easily determined visually.

Figure 3 (a) 6 ports) is a coated optical fiber,
17 Distance ratio Xg/Xt, Yq/Yt (7) vs. %
ffi t1. This shows the relationship between the eccentric direction (horizontal axis) and the logarithm value (vertical axis).

The variation at this time is the amount of eccentricity (eccentricity E).

In addition, the distance from the center of the coated optical fiber to the screen is 50 mm, the outer diameter Df of the optical fiber, the outer diameter DC1 of the coating layer, the refractive index Nf of the optical fiber, and the refractive index N of the coating layer.
These state parts, such as c and eccentricity E, are shown in the figure.

As can be understood from Figure 3 (a) 6 mouths), the fln
(XR/Xi), in (YR/Yl) closely approximates the trigonometric function of one eccentric angle by M degrees.

Therefore, the amount of eccentricity and the angle of eccentricity can be determined by simple functional calculation using the following formula (the linear monomial described above).

in (XR/XL)=A-sinO=-(1)I
n (YR/YL)-1 A-cos O=
... = In the formula (2), A is the amplitude of the above trigonometric function, and is a state quantity determined by the outer diameter of the outer circumference, the refractive index, and the amount of eccentricity.

As is clear with reference to FIG. Angle formed with line segment 2 passing through the center of the outer shape and the center of the shaft center.

Specifically, it is as follows.

The following equation is derived from equations (1) and (2).

θ=jan-1(-4n(XR/Kari)/bunn(YR
/YL) 1... (3) Substitute the value of 0 into either equation (1) or (2) to find A.

A=f (outer diameter of the outer periphery, refractive index, amount of eccentricity), of which the outer diameter is known (measured via the outer diameter measuring device 6z) and the refractive index is known (measured by the refractive index setting device 60). settings), so
Based on the value of A, the amount of eccentricity can be calculated.

As mentioned above, by performing flif n using equations (1) and (2), the eccentricity between the optical fiber and the coating layer can be calculated for various coated optical fibers with different specifications regarding the outer diameter and refractive index of the coating layer. Similarly, for a transparent hollow pipe, the eccentricity between its axial center (hollow part) and outer circumferential part (viz circumferential wall) can be found, and in this way, a huge amount of data on the object to be measured can be collected. is resolved.

By the way, Kihatsu! When irradiating a light beam toward the object to be measured from the X-axis direction and the Y-axis direction in the blade method, the irradiation position of the light beam on the object to be measured is adjusted to: A so that the brightness level of the scattering pattern is maximized. In such a case, the object to be measured and the spotlight of the light beam are perfectly matched, and the predetermined eccentricity can be determined accurately.

In this case, the brightness of the scattering pattern is reduced to 1.
6 (closely monitor the monitor so that its brightness level is maximum,
A method for adjusting the irradiation position of the light beam on the object to be measured.The total width of the scattering pattern is calculated514, and the irradiation position of the light beam on the object to be measured is adjusted so that the band width is the same on the left and right sides. For example, how to do this.

1 shot 1y1 effect" As explained above, when using the method of the present invention, the axial center part and the outer peripheral part covering the axial center part have translucency, and the refractive index of the axial center part and the outer peripheral part is Using mutually different elongated bodies as objects to be measured, projecting the X-axis side scattering pattern and the Y-axis side scattering pattern of the objects to be measured on respective predetermined screens,
i n (XR/XL), I for these scattering patterns
When measuring the eccentricity of the shaft center and outer circumference by calculating n(YR/Yt), the eccentricity is calculated by calculation based on the predetermined formulas (1) and (2), so it is easy to use. The eccentricity can be accurately measured using a suitable calculation means.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of an embodiment of the method; FIG. 2 is an explanatory diagram of scattered light generated when a light beam passes through the axial center and outer circumference of the object to be measured; FIGS. 3A and 3B are explanatory diagrams showing the relationship between the distance ratio of the scattering pattern and the eccentric angle in logarithmic values, and FIG. 4 is an explanatory diagram of the conventional method. 30...Elongate body (object to be measured) 31...Axis center portion of the elongate body 32...Outer peripheral portion 50 of the elongate body...Light Irradiation system 51... Emitter 52... Spectrometer 53... Reflector (X axis) 54... Reflector (Y axis) 55... ... Screen (Xi) 5B ... Screen (Y axis) 57 ... Optical system (X axis) 58 ... Optical system (Y axis) 59 ... ...Computational system agent Patent attorney Yoshio Saito Figure 2 Figure 3 (a)

Claims (1)

[Claims] 1. A long body covered with an axial center portion and an outer periphery covering the axial center portion having translucency, and in which the axial center portion and the outer periphery have mutually different refractive indexes. If the object to be measured is a line segment passing through the axis of the object to be measured as the O axis, and two line segments that intersect the O axis at a nearly right angle are the X axis and Y axis, then on these X and Y axes The light irradiation section and the screen of the light irradiation system are placed facing each other with the object to be measured in between, and the light beams are directed from the light irradiation sections on the X-axis and the Y-axis toward the object to be measured. The scattering pattern of the light transmitted through the outer periphery and axial center of the object to be measured is projected on each screen on the X-axis and Y-axis, and the scattering pattern projected on the screen on the X-axis is Each distance from the center of the pattern to both ends is X_L, X_R, and the distance ratio X
The natural logarithm of _R/X_L is ln(X_R/X_L), the distances from the center to both ends of the scattering pattern projected on the screen on the Y axis are Y_L, Y_R, and the natural logarithm of the distance ratio is ln( Y_R/Y_L), each of the above-mentioned scattering patterns is captured by an optical means, information on these scattering patterns is input to a processing system, and the above-mentioned ln(X_R/X_L), ln
In the method of measuring the mutual eccentricity between the shaft center and the outer circumference by calculating (Y_R/Y_L), ln(X_R/X_L)=A・sinθ (1) l
n(Y_R/Y_L)=-A・cosθ (2) (where A is the amplitude of the above trigonometric function, the state quantity determined by the outer diameter, refractive index, and eccentricity of the outer circumference, and θ is Information on each scattering pattern is calculated based on the eccentricity angle of the object to be measured, which is the angle formed by the reference line passing through the center of the object's outline and the line segment passing through the center of the object's outline and the center of the axis. A method for measuring the eccentricity of a translucent elongated body, characterized in that the eccentricity is determined by calculating the eccentricity using the arithmetic processing system. 2. Claim 1, in which the elongated body having translucency is composed of an optical fiber and a transparent coating layer formed on the outer periphery of the optical fiber.
A method for measuring the eccentricity of an elongated body having translucency as described in 2. 3. The method for measuring the eccentricity of a translucent elongated body according to claim 1, wherein the translucent elongated body is a transparent hollow pipe. 4 Each light irradiation end of the mutually independent light irradiation system is placed on the X axis,
2. The method for measuring the eccentricity of a translucent elongated body according to claim 1, wherein the light beam is arranged on the Y-axis and a light beam is irradiated from each of the light irradiation ends toward the object to be measured. 5. The light irradiation system is equipped with one light projecting means, one spectroscopic means, and two reflecting means, and the light beam emitted from the light projecting means is split into spectra by the spectroscopic means, and the separated light is split by the respective reflecting means. Claim 1 in which the reflected light is reflected in the X-axis direction and the Y-axis direction, and each reflected light is irradiated toward the object to be measured.
A method for measuring the eccentricity of an elongated body having translucency as described in 2.