JPS61209340A - Optical measuring apparatus - Google Patents

Abstract

PURPOSE:To make it possible to simultaneously measure a basis wt. or a thickness, moisture and hue with high accuracy, by providing three filters for transmitting three measuring wavelengths and performing operation by three measuring wavelength components. CONSTITUTION:A filter 51 for transmitting a first measuring wavelength lambda1 absorbing no moisture, a filter 52 for transmitting a second measuring wavelength lambda2 absorbing moisture and filters 53, 54 for transmitting the third measuring wavelength lambda3 of a visible light region are mounted and a rotary sector 5 rotated by a motor M is provided. The light of a light source 1 is projected to an object 3 to be measured through a projection lens 2 and transmitted light or reflected light thereof enters a detection element 6 through a condensing lens and the rotarly sector 5 and first, second and third signals e1, e2, e3 corresponding to the components of first, second and third measuring wavelengths lambda1, lambda2, lambda3 being the outputs of said detection elements 6 enter sampling hold circuits 81, 82, 83 and, subsequently, the basis wt. or thickness, moisture and hue of the object 1 to be measured are measured from the signals e1, e2, e3 by dividers 91, 92.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical measuring device that can simultaneously measure a plurality of various properties of an object to be measured.

[Conventional technology]

Traditionally, light has been used to determine the basis weight, thickness, moisture content, etc. of the object to be measured.
Optical measuring devices such as moisture meters and thickness meters that separately measure properties such as color tone are known.

[Problems to be solved by this invention] However,
When trying to measure various properties at the same time, separate devices must be installed at different locations, which increases the size of the device and makes it difficult to simultaneously measure each polarity at the same location on the object being measured. Ta.

In view of the above points, it is an object of the present invention to provide an optical measuring device that can simultaneously measure the basis weight, thickness, moisture content, color tone, etc. of an object to be measured using one device.

[Means for Solving the Problems] The present invention provides a first measurement wavelength that does not absorb moisture, a second measurement wavelength that absorbs moisture, and a third measurement wavelength in the visible light region. Each wavelength component is measured, and the basis weight or thickness is determined from the first measurement wavelength component, the moisture content is determined from the ratio of the second measurement wavelength component and the first measurement wavelength component, and the third measurement wavelength component and the first measurement wavelength are determined. This is an optical measurement device that measures color tone based on the ratio of components.

[Embodiment] FIG. 1 is a configuration explanatory diagram showing an embodiment of the present invention.

In the figure, 1 is a light source for projecting light, and the light from this light source 1 is
Light is projected onto the object to be measured 3 by the projection lens 2, and its transmitted light or reflected light is collected by the condensing lens 4, and the rotating sector 5 rotated by the motor M is provided with a diameter of approximately 1.0 μm that does not absorb moisture. A filter 51 that transmits a first measurement wavelength λ1 such as λ1, a filter 52 that transmits a second measurement wavelength λ2 of approximately 0.95 μm that absorbs moisture, and a filter 52 that transmits a second measurement wavelength λ2 of approximately 0.8 to 0.5 μm in the visible light region. The light enters the detection element 6 via a filter 53 that transmits the third measurement wavelength λ3. Note that the filter 54 may be used for measurement at a fourth measurement wavelength different from the third measurement wavelength λ3 in the visible light region, or may be used as a preliminary measurement for other optical properties. The detection signal of the detection element 6 is amplified by an amplifier 7 to produce first, second, and third signals e1, e2, and e3 corresponding to the components of the first, second, and third measurement wavelengths λ1, λ2, and λ3. However, the first, second and third sample and hold circuits 81,
It is held at 82.83. Then, the basis weight or thickness of the object to be measured 3 is measured from the signal e1 corresponding to the component of the first measurement wavelength λ1 of the first sample and hold circuit 81, and the second measurement wavelength of the second sample and hold circuit 82 is measured. The first divider 91 calculates the ratio e2/el between the signal e2 corresponding to λ2 and the signal e1 of the first sample hold circuit 81.
, the moisture content of the object to be measured 3 is calculated, and the third measurement wavelength λ of the third sample hold circuit 83 is calculated.
3 and the first sample hold circuit 8
The ratio e3/'e1 of 1 to the signal e1 is calculated by the second divider 92, and the color tone and the like are measured.

In this way, properties such as basis weight or thickness, moisture content, color tone, etc. of the object to be measured 3 can be measured simultaneously.

Note that the functions of the sample and hold circuits 81, 82, 83, dividers 91, 92, etc. may be realized using arithmetic means such as a microcomputer including a memory, a personal computer, etc.

FIG. 2 shows another embodiment, in which measurement light from an object to be measured 3 is focused by a condenser lens 4, separated by a spectroscopic means 10 such as a prism or a diffraction grating, and then applied to an image sensor such as a COD. Light of different wavelengths enters each of the 11 elements. The signals corresponding to each wavelength component of this image sensor 11 are
The signals are sequentially read out, and a calculation means 12 such as a microcomputer performs calculations on the signals corresponding to the measurement wavelength components as explained in FIG. 1, and measurements are performed.

[Effects of the Invention] As described above, the present invention performs calculations using multiple wavelength components, so the basis weight, thickness,
The properties of the object to be measured, such as moisture content and color tone, can be measured simultaneously and with high precision using a single device, which is small and inexpensive.

[Brief explanation of drawings]

FIGS. 1 and 2 are configuration explanatory diagrams showing one embodiment of the present invention.

Claims (1)

[Claims] 1. Measuring each wavelength component from the object to be measured using a first measurement wavelength that does not absorb moisture, a second measurement wavelength that absorbs moisture, and a third measurement wavelength in the visible light region; The basis weight or thickness is determined from the first measurement wavelength component, the moisture content is determined from the ratio of the second measurement wavelength component to the first measurement wavelength component, and the moisture content is determined from the ratio of the second measurement wavelength component to the first measurement wavelength component.
An optical measurement device that measures color tone from the ratio of measured wavelength components. 2. The first, second, and third measurement wavelengths are approximately 1.0
2. The optical measurement device according to claim 1, wherein the optical measurement device uses a diameter of about 0.95 μm, about 0.8 to 0.5 μm.