JPS63295945A - Glossiness measuring apparatus - Google Patents

Abstract

PURPOSE:To enable accurate evaluation of surface character of a surface to be measured with high spatial resolution and a wide measuring range, by arranging a projection means, a detecting means, a processing means and the like. CONSTITUTION:Parallel luminous flux from a projection means 2 is made incident slantly into a surface 1 to be measured via a slit 7 for adjusting the width of the luminous flux and a collimation lens 8 and the reflected light thereof is received by a detection means 3 provided on the opposite side via an optical system 4 to detect. The means 3 has a first detection means 31 with high spatial resolutions to detect at least a directly reflected light component out of that and components near it in the reflected light and a second detection means 32 with a detection level enough to match the light intensity of components separated from the directly reflected light component. Signals of light intensity distributions of the directly reflected light component and components near it as detected with the means 31 and 32 and a light intensity signal of a scattered light component are brought into a processing means 5 to compute, thereby enabling accurate evaluation of surface character with the measurement of waviness and blur of the surface 1 being measured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a gloss measuring device that quantitatively evaluates the glossiness, sharpness, etc. of a finished surface such as a paint film surface.

[Conventional technology]

JIS Z 874L or A
A specular gloss measurement method specified in STM E167 and the like is used. In addition, various types of glossmeters such as angle glossy needles and microscopic glossy needles conforming to these standards have also been manufactured. These gloss meters irradiate a surface to be measured with a parallel beam of light, receive the reflected light with a single light-receiving element, and determine the degree of specular gloss from the intensity of the light.

Glossiness is usually characterized by the peak intensity of specularly reflected light, the spread and slope of the distribution near the specularly reflected light, the intensity of wide-angle scattered light, the ratio of the peak intensity to the intensity of wide-angle scattered light, and the like.

However, in the above method, since the light receiving element is single and the light receiving angle is large, it is usually possible to measure only the light intensity including specularly reflected light and reflected light in the vicinity thereof. There are some devices, such as a glossy variable angle needle, that can measure the spread of the distribution by moving the light receiving element, but their angular setting resolution is coarse, around 1°, so the necessary spatial resolution cannot be obtained, and the angle of change cannot be measured. There are also problems such as (mechanical scan) taking a long time.

With the recent demand for paints with high gloss, including automotive paints, the importance of evaluating the degree of pigment dispersion in the paint manufacturing process and the gloss of the final finished paint film is increasing. However, evaluation using the above method is becoming insufficient.

Therefore, as an alternative to this, various standards such as ASTHE430 and new methods and devices have been proposed.

For example, the invention described in Japanese Unexamined Patent Publication No. 145436/1986 is one of the new methods and apparatuses described above, and has the configuration shown in FIG.

That is, a parallel light beam is made perpendicularly incident on the surface to be measured 1 from the light projecting means 2, and the reflected light is extracted out of the parallel light beam by the beam splitter 6. The reflected light taken out passes through the lens 4 to the photodiode array 21.
The photodiode array 21 converged on the surface of the light detects the light intensity of the specularly reflected light component and the light intensity of the component shifted by about 0.5 to 2'' from the specularly reflected light component of the converged light. Then, the light intensity of these two components, or
The ratio is calculated and displayed by the processing means 5. In the figure, numeral 22 is a luminous flux adjusting means for converting the light from the light projecting means into a parallel luminous flux, and 23 is a display for displaying the calculation results.

From the light intensity of the detected specularly reflected light component, it is possible to know the difference in gloss on the surface to be measured, which is close to a mirror surface, and from the light intensity distribution pattern within a range of about ±1", which includes the specularly reflected light component, In addition, the ratio of the light intensity of the specularly reflected light component to the light intensity of the component that is shifted by about 2 degrees from this specularly reflected light component can be used to determine the surface shape of the paint film (so-called undulating state). It is possible to know the state of so-called blur, such as the state of dispersion of scattering particles.

[Problem that the invention seeks to solve]

However, the photodiode arrays used in these methods and standards usually have a spatial resolution of about 0.36 (chicken bone resolution), and the specular reflection light component has a spread of only about ±16. There is a problem in that the resolution is not sufficient to measure the light intensity distribution in the vicinity. In this way, if the resolution of the element that detects the light intensity distribution of the specularly reflected light component and its neighboring components with a spread of around 1° is low, it becomes difficult to know the exact state of the undulation.

Furthermore, a reflected light distribution model from the coating surface is shown in Figure 6. In this model, the light intensity of the specularly reflected light component and its neighboring components are determined by the intensity of the other reflected light (hereinafter referred to as the "scattered light component").
Since the light intensity is significantly larger than that of the scattered light component, measuring it with a single photodiode array would result in insufficient sensor cleanliness, making it impossible to accurately measure the light intensity of the scattered light component. This means that it is difficult to know the state of blur on the surface to be measured.

As described above, with these methods and standards, it is not possible to measure both undulations (such as citrus skin) and blur, which are important factors on the surface to be measured, with sufficient accuracy. On the surface to be measured, there is a problem in that the two influence each other, making it impossible to accurately evaluate the surface properties.

This invention was made in view of the above circumstances, and
It has extremely high spatial resolution and wide measurement range.
It is an object of the present invention to provide a glossiness measuring device that can accurately evaluate the surface properties of a surface to be measured.

[Means for solving problems]

In order to achieve the above object, the glossiness measuring device of the present invention is shown in FIGS. 1(a) to (C) and FIG. 2(a).
) to (C), the light projecting means includes a light projecting means 2 that generates light directed toward the surface to be measured l, and a detecting means 3 that receives and detects the reflected light from the surface to be measured, and the light projecting means An optical system 4 for converging the light on the detection means is provided on the path of light from 2 to the detection means 3, so that the detection signal from the detection means is processed by the processing means 5 and the light intensity is measured. It has become. The detecting means 3 is a first detecting means 3 having a high spatial resolution that detects at least the specularly reflected light component of the specularly reflected light component in the reflected light and its neighboring components.
1 and a second detection means 32 having a detection level matched to the light intensity of a component distant from the specularly reflected light component.

[For production]

The present invention will be described in detail below with reference to the drawings showing examples.

The configuration of the path of light from the light projecting means 2 to the detecting means 3 via the surface to be measured 1, the position of the optical system 4, etc. is not particularly limited in this invention. For example, as shown in FIG. 1 (al to (C)) and FIG. 2 (al to (C)), various configurations can be adopted.

In the embodiments shown in FIGS. 1(a) and 2(al), the light incident on the surface to be measured 1 from the light projecting means 2 is a parallel beam of light, and the optical system 4 consisting of lenses etc. It has a configuration in which the light reflected by the detector is converged onto the detection means 3.

In the embodiment shown in Fig. 1fa), the parallel light beam from the light projecting means 2 is made obliquely incident on the surface to be measured 1, and then the reflected light is received and detected by the detection means 3 provided on the opposite side. It has become. In addition, in the embodiment shown in FIG.
After making the parallel light beam from
The reflected light is taken out of the parallel beam using a beam splitter 6, and is received and detected by a detection means 3 provided there. These configurations, especially in Figure 2 (al
The configuration is almost the same as that of Japanese Patent Application Laid-Open No. 145436/1983 described above.

Although a laser is used in these embodiments as the light projecting means 2 that emits such a parallel light beam, ordinary diffuse light projecting means such as a halogen lamp or an arc lamp, a condenser lens, a slit or a pinhole, and a collimator may also be used. A lens consisting of a mate lens may also be used. Moreover, among these, slits and pinholes can be omitted.

The slit 7 and the collimating lens 8 in the embodiments shown in these figures are used to adjust the width of the parallel light beam, and are not used to convert the light from the normal light projecting means into a parallel light beam. Therefore, these slits 7 and collimating lenses 8 are not necessarily necessary as long as the light projecting means is a laser.

The parallelism of these parallel light beams is not particularly limited in the present invention, but it is preferably 0.05° or less, which is the parallelism required for such parallel light beams, and 0.0
More preferably, it is 1' or less.

In the embodiment shown in FIG. 1(b) and FIG. 2(bl), the light from the light projecting means 2 is a convergent beam that converges on the surface to be measured l, and the light reflected from this surface to be measured is used in the optical system. 4, the light is refocused onto the detection means 3. In this configuration, the light irradiated onto the surface to be measured 1 is in the form of a point or a line.

The other configurations are the same as those of the previous two embodiments; the embodiment shown in FIG. 1(b) makes the light beam obliquely incident on the surface to be measured, and the embodiment shown in FIG. 2(b) In this embodiment, the light beam is incident perpendicularly onto the surface to be measured. These configurations can be used to cut out the influence of waviness among the surface properties of the surface to be measured and measure only the state of blur, as will be described later.

The light from the light projecting means 2 is converged onto the surface to be measured 1 by a slit 7 (or pinhole) and a converging lens 9. As the light projecting means 2, a laser is used as in the previous embodiment, but the slit 7 is
When obtaining a convergent light beam using the converging lens 9, the diffused light projecting means such as the halogen lamp or arc lamp can be used as is. In that case, a condenser lens may be interposed between the diffused light projection means and the slit 7. Further, when the laser is used as a light projecting means, the slit 7 is not necessary, and a convergent light beam can be obtained with only the converging lens 9.

In the embodiments shown in FIGS. 1(C) and 2(C), the light incident on the surface to be measured 1 from the light projecting means 2 is converged in advance by the optical system 4 so that it is converged on the detecting means 3. The case where it is a luminous flux is shown. The other configurations are the same as those of the above embodiments, and the embodiment shown in FIG. 1(C) makes the light beam obliquely incident on the surface to be measured, and the embodiment shown in FIG. 2(C)
In this embodiment, the light beam is made perpendicular to the surface to be measured.

In these configurations, the surface to be measured 1 is as shown in FIG. 1(a).
, a light beam with a certain spread similar to the parallel light beam in the embodiment of FIG. 2(a) is irradiated. Furthermore, the light beam does not need to be a strictly parallel light beam. It is only necessary that the light converges on the detection means 3. Therefore, as shown in these figures, the light projecting means 2
Not only does this eliminate the need to use expensive lasers, but the entire device can also be simplified. For example,
In the embodiments shown in these figures, a diffused light projecting means such as a halogen lamp or an arc lamp is used as the light projecting means 2, and the light from the light projecting means is transmitted to the optical system 4 via a condenser lens 10 and a slit 7. Supplied. In this way, the configuration of the embodiment shown in FIGS. 1(C) and 2(C1) is, so to speak, a simplified version of the embodiment shown in FIGS. 1(a) and 2(al). In addition, in these embodiments, the theoretical width C1 of the convergent light on the detection means (assuming there is no scattered light) and the spatial resolution d of the first detection means 31, which will be described later, are d〉ω It is preferable that there is a relationship between .

In the present invention, the detection means 3 that receives and detects the reflected light from the surface to be measured 1 detects at least the specularly reflected light component of the specularly reflected light component in the reflected light and the component in the vicinity thereof. It is characterized by having two elements: a first detection means 31 with high resolution and a second detection means 32 having a detection level matched to the light intensity of the component far from the specularly reflected light component. , which will be discussed in detail below.

The first detection means 31 is for detecting the distribution of light intensity with high spatial resolution, and consists of a specularly reflected light component and components in the vicinity of the specularly reflected light component of the reflection pattern shown in FIG. It is used to know the detailed shape of the peak and its light intensity. Therefore, the higher the spatial resolution of this first detection means 31, the more preferable it is, but practically it is preferable that it be within the range of the following formula. In the following formula, d is the minimum spatial distance that can be measured by the first detection means 31, and l is the distance from the surface to be measured 1 to the first detection means 31.

0.1°≧tan −' − When a linear image sensor is used as the detection means 31,
If you visualize this in a diagram, it becomes Figure 4. 313 in the diagram...
represents each cell of the linear image sensor constituting the first detection means 31.

The detection angle of the first detection means 31 is not particularly limited in the present invention, but in order to detect only the specularly reflected light component and components in its vicinity and not detect other scattered light components, the following steps are required: It is preferably within the range of the formula. Note that r in the following formula represents the spatial distance range that can be measured by the first detection means 31, as shown in FIG. As in the previous equation, represents the distance from the surface to be measured to the first detection means.

Although the first detection means 31 having the spatial resolution and detection angle as described above is not limited to this,
For example, photodiode array, MOS or C
A linear image sensor such as a CD, a concentric image sensor, a combination of a linear fiber bundle and a plurality of discrete photodetectors, a combination of a discrete photodetector with a minute aperture and a mechanical scanning mechanism, etc. can be used. As the first detection means 31, the linear image sensor, the concentric image sensor,
When using a photodiode array, etc., in order to achieve the above-mentioned spatial resolution range, depending on the distance to the surface to be measured, for example, a cell spacing of 501 rm pitch or a 28-pitch cell spacing, etc. It is sufficient to use one in which the value is in μm. In the case of using a linear fiber bundle, the pitch of the fiber tips may be set to the same distance. Furthermore, when using a discrete photodetector with a minute aperture, the distance between the minute apertures may be set to the same extent.

The first detection means 31 having the above-described configuration can detect a light intensity distribution pattern in a range of approximately ±1'' including the specularly reflected light component described above, in units of 0.16 or less.
It becomes possible to know the surface shape of the surface to be measured, such as the undulation state, much more accurately than with conventional methods.

The reason why the undulating state of the surface to be measured can be determined from the light intensity distribution pattern in the range of approximately ±1° including the specularly reflected light component is as follows.

That is, on the surface 1 to be measured, the above-mentioned FIG.
When you irradiate a light beam with a certain degree of spread, such as a parallel light beam as shown in a) or a light beam as shown in Figures 1 (C) and 2 (C1),
When the surface to be measured is a completely smooth surface, all the light rays making up the luminous flux become specularly reflected light components.

Therefore, the light intensity distribution pattern in the range of around ±1° that includes the specularly reflected light component is theoretically composed of only the specularly reflected light component (in reality, it is caused by light diffraction, aberrations of optical parts such as lenses, etc.). (However, due to this influence, it is not completely composed of specularly reflected light components.) On the other hand, if there is an undulation such as an orange skin on the surface to be measured, the angle at which the light rays forming the luminous flux are reflected will be changed depending on the undulation. Therefore, looking at the light intensity distribution pattern, the ratio of the specularly reflected light component decreases, and the ratio of other components increases. Therefore, by setting the ratio of the specularly reflected light component on a perfectly smooth surface to 100 and examining how much the ratio of the specularly reflected light component has decreased from there, it becomes possible to identify the swell state.

On the other hand, in the configurations shown in FIGS. 1(b) and 2(bl), it is possible to cut out the influence of undulations on the surface to be measured and measure only the state of blur. This is for the following reason.

As described above, the state of undulation can only be measured when the light beam irradiated onto the surface to be measured spreads.

On the other hand, in order to check the state of blur on the surface to be measured, it is necessary to measure only the scattered light component with the second detection means 32, as will be described later. However, if there is a spread in the light beam irradiated onto the surface to be measured, the surrounding light rays will reach the second detection means 32 due to the undulations of the surface, affecting the scattered light intensity. This effect increases as the spread of the luminous flux and the degree of undulation increase. For example, for samples with many fine undulations or samples with poor surface conditions, if the luminous flux spreads, accurate measurements cannot be made. (Note that if the undulation is large enough, there will be no such effect, so it is possible to measure even if the luminous flux spreads.

Therefore, as shown in Figure 1 (b) and Figure 2 (b), the light beam irradiated onto the surface to be measured is made into a convergent beam that converges on the surface to be measured, thereby eliminating the spread. However, the swell will not affect the detection of the scattered light intensity by the second detection means 32. Therefore, the spread of the light beam on the surface to be measured is preferably as small as possible. Practically speaking, it is preferable that the range is within the range expressed by the following formula.In the following formula, ω2 is the width of the light beam on the surface to be measured, m! is the imaging magnification of the imaging means 4, and d is The intervals between the cells constituting the first detection means are shown.

ω2 〈 □ By using such an optical system, for example, by calculating the ratio between this peak intensity and the above-mentioned scattered light intensity, it is possible to measure the state of blur on the surface to be measured while cutting out the effects of undulation. You will be able to do so. Note that the peak intensity can be represented by the light intensity of the specularly reflected light component, or can be represented by the light intensity of the specularly reflected light component and its neighboring components.

The second detection means 32 for detecting the intensity of scattered light as described above needs to measure the scattered light component in the reflection pattern shown in FIG. 6 at a detection level commensurate with the reflected light component. Therefore, it is preferable that the second detection means 32 has higher sensitivity than the first detection means 31.

As mentioned above, it is important to know the light intensity of scattered light, not the light intensity distribution. Moreover, as shown in FIG. 6, the scattered light to be detected by the second detection means 32 often has a substantially uniform intensity distribution. Therefore, the spatial resolution of this second detection means 32 does not need to be as high as that of the first detection means 31 described above.
It suffices if it is the same as the conventional one, that is, within the range of the following formula. In the following equation, d' is the minimum spatial distance that can be measured by the second detection means, and l' is the distance from the surface to be measured to the second detection means.

In the method of JP-A-61-145436 mentioned above,
The detection angle (spatial detection range) is approximately 0.5 to 20'', and even in ASTM E430, the detection angle is ±
However, when the detection angle is narrow like this, it becomes difficult to detect the scattered light intensity.This is because the scattered light is weak as mentioned above, and the light receiving area is small. The main reasons are that if the area is too narrow, the amount of light received will be insufficient, and the part of the scattered light near the specularly reflected light component will be affected by the undulations mentioned above, making it impossible to accurately detect the intensity of the scattered light.

Therefore, in order to increase the amount of light received by widening the light receiving area, it is preferable that the second detection means 32 be able to detect scattered light components at as wide an angle as possible. Therefore, although the upper limit range of the detection angle should not be limited in the present invention, if the detection angle is too wide, there is a high risk that components other than the scattered light will be detected as noise. Therefore, it is preferable that the detection angle falls within the range of the following formula. In the following formula, r' is the spatial distance range that can be measured by the second detection means, θ is the incident angle, and l
As in the previous equation, '' represents the distance from the surface to be measured to the second detection means.

The second detection means 32 having the above-described spatial resolution and detection angle may include, but is not limited to, a single or multiple discrete photodetector, a discrete photodetector, and a mechanical scanning device. A combination of mechanisms, etc. can be used. Alternatively, a photodiode array, a linear image sensor with a normal pitch, a concentric image sensor, or the like may be used.

Since the second detection means 32 having the above-mentioned configuration is a separate element from the first detection means 31, its sensitivity setting can be easily changed, and the specular reflection light component and its vicinity can be easily differentiated. It is possible to accurately know the intensity of the scattered light component, which is much lower in intensity than the other components. Therefore, the degree of blurring of the surface to be measured, which is the ratio of the intensity of the scattered light component to the intensity of the specularly reflected light component, can be determined more accurately than in the conventional method.

The first detection means 31 and the second detection means 32 as described above
The signals of the light intensity distribution of the specularly reflected light component and its neighboring components, as well as the light intensity signal of the scattered light component, detected by the above are taken into the processing means 5 and calculated to eliminate undulations and blur on the surface to be measured. Condition is measured.

Although the configuration of the processing means 5 is not particularly limited in the present invention, it can be configured as shown in FIGS. 3(al) and (b), for example.

In the processing means 5 of FIG. It has a configuration in which the signal is taken into the arithmetic circuit 5b via a multiplexer 5C and an amplifier 5d.

A drive connecting the first detection means 31 and the arithmetic circuit 5b/
The amplifier 5a literally also serves as a driver for this first detection means 31. Further, the multiplexer 5c connecting the second detection means 32 and the amplifier 5d is used in the second detection means 32 composed of many photodetectors, for example, a photodiode array. It works to multiplex the light intensity signal from the photodetector and convert it into a signal of the same mode as the light intensity distribution signal from the first detection means 31, and then input it into the calculation means 5b.

The processing means 5 in FIG. 3(b) is the same as in the case of FIG. ing. In the illustrated processing means 5, the second detection means 32
This is used when each photodetector is made up of a single independent photodetector, and the light intensity signal from each photodetector is connected to the arithmetic circuit 5b via an amplifier 5d. This is different from the case of

In addition, the drive/drive used in these processing means 5
As the amplifier 5a and the amplifier 5d, it is preferable to use an automatic range amplifier or a programmable amplifier in order to ensure a wide range.

In the glossiness measuring device of the present invention having the above configuration, it is preferable to measure the sample with the light emitting/receiving system placed in a dark room or in a case in order to avoid the influence of external light. . Further, as a standard plate for measurement, for example, a black glass plate or the like may be used to calibrate the device and check for abnormalities.

〔Example〕

(Experiment 1) In order to prove that the degree of blur on the surface to be measured can be determined from the ratio between the peak intensity in reflected light and the intensity of scattered light, the following experiment was conducted.

As shown in FIG. 7, the light projecting means 2 is an l1e-Ne laser (output 1 mW, beam diameter 0.8 w1), 1 wavelength 62
3,8 nm), and the light from this light projecting means is directed to the surface to be measured 1 at an angle of θ. = 20°, and the reflected light is transferred to the photodiode 3' (MA97A manufactured by Anri Corporation,
Light receiving window 1). A measurement optical system was created that receives light at an angle of 3uiφ and a light receiving angle θ' = 3.2°. In addition, as shown in the figure, the photodiode 3' has an angle (
θ) can be changed, and this photodiode 3' is connected to an optical power meter 5' (ML 93 A manufactured by Anri Corporation). The measuring optical system has a function corresponding to the peak intensity measuring function of the first detecting means and the second detecting means of the glossiness measuring device of the present invention.

Next, five types of paints were prepared in which the following components were dispersed using a schisand mill using glass peas as a dispersion medium, and the dispersion time of the pigment paste was varied to vary the degree of blurring of the resulting coating film.

(Paint components) Pigment: Quinacridone Red Paste Resin Niacrylic Resin Solvent: Xylol These paints are applied to a glass plate with a 4 rnil doctor blade, dried to form a coating film, and used as the surface to be measured. Five types with different degrees of blur are used. A sample was prepared.For the obtained sample, the intensity of reflected light at each light reception angle (0'≦θ≦800) was measured using the measurement optical system described above.

The results are shown in FIG. Note that each symbol in the figure corresponds to each sample as shown below.

10-0-2 Dispersion time 60 minutes -・--: 〃 100 minutes 10-0-: 〃 100 minutes 1 Mumu: 300 minutes 1-1: 420 minutes Also, from the obtained data, specular reflection Light component (θ=20”
) (7) The ratio between the light intensity and the light intensity of the scattered light component at θ = 25°, 30”, and 35° was calculated. This calculation result and the image contrast (NSIC*
”), as shown in Figure 9, they line up almost on a straight line in all cases, and the ratio of the peak intensity in the reflected light to the intensity of the scattered light is well matched to the contrast of the image, which is a parameter of blur. It was found that they matched.The symbols in the figure are the same as in FIG. 8 above.

The image contrast (NSIC*) referred to here refers to the spatial light of the imaged waveform when a rectangular wave pattern is projected onto the imaged surface by the imaging optical system through reflection on the surface to be measured. Among the power spectra obtained by Fourier transforming the intensity distribution, it is derived from the intensity of the power spectrum of the fundamental spatial frequency, and is expressed as a percentage when the intensity of the black glass plate, which is the reference plate, is taken as 100. The imaging waveforms of each sample above are shown in FIG.
It looks like 1. Each figure corresponds to each sample as shown below.

Figure 1O (a) Bidispersion time 60 minutes Same figure (bl: // 120 minutes Same figure (C
): 〃 180 minutes Same figure (d):
// 300 minutes Same figure (e): 〃
420 minutes (Experiment 2) The following experiment was conducted to prove that the degree of undulation on the surface to be measured can be determined from the light intensity distribution of the specularly reflected light component and its neighboring components.

The measurement optical system shown in Fig. 1) was created using the following components. This optical system has a function corresponding to the first detection means of the glossiness measuring device of the present invention.

Slit 7 width 5μm Collimating lens 8: f-200m layer F3.5 Optical system (lens) 4: f=200m+*F3.5 First detection means 31: Photodiode array pisochi 2
Using a measurement optical system with 81 rm and 512 or more cells, the light intensity distribution (peak) of the specularly reflected light component and its neighboring components was measured for samples having measurement surfaces in various undulating states.

Figure 12 (a) shows the relationship between the opening angle (denoted as θ% in Figure 1) corresponding to 2 of the half-width H of the obtained peak and the power spectrum sum of the cross-sectional curve of the undulation of the sample.
Shown in (b). In addition, No. 121b) shows the shape of the peak of each sample. Note that each symbol in the figure corresponds to each sample below.

◎: Black glass plate (no undulations) ◆: Solid red △: Solid white The sum of the power spectra of the cross-sectional curves of the undulations is the sum of the power spectra of the cross-sectional curves of the sample surface obtained by Fourier transformation, in the range corresponding to the undulations. The sum ΣPi of the power spectra of the components having a period is expressed as ΣPi.

In Fig. 12(a), the period of the spectrum is 0.257 to 1.
). The relationship between the sum (relative value) of the powers of the 52 fin components and θ% is shown in Figure (b) when the period of the spectrum is 0.2.
Sum of powers of components from 57 to 9.22 m (relative value) and θ%
I'm worried about the relationship.

From the results shown in the above figures, it was found that the degree of undulation on the surface to be measured and the state of the light intensity distribution of the specularly reflected light component and its neighboring components match well.

(Experiment 3) The following experiment was conducted to prove that by using a light beam that converges on the surface to be measured, the effect of undulation can be eliminated and blur can be measured more accurately.

The measurement optical system shown in FIG. 13 was created using the following components. This optical system has a function corresponding to the first detection means of the glossiness measuring apparatus of the present invention in FIG. 1 (bl).

Slit 7: Width 5 - Converging lens 9: f=551m Fl, 8 Optical system (lens) 4: f=55mm F1.8 First detection means 31: MOS image sensor pitch 28
μm Number of cells: 512 Using the measurement optical system described above, the light intensity distribution in a range of ±0.3° centered on the specularly reflected light component was measured for four measurement surface samples consisting of a combination of blur and undulation. Note that, among the above-mentioned samples, the degree of blur in the sample with blur and the degree of undulation in the sample with waviness were approximately the same among the respective samples. The results are shown in Figure 14 (a) to (dl
Shown below.

For comparison, the measurement optical system (
Measurements were also made in the same way using the first detection means (corresponding to the first detection means in FIG. 1(a)). These results are shown in Figure 14(e)-(
Shown in h).

Each figure corresponds to each sample as shown below.

As shown in the figure, in the measurement optical system shown in Figure 1), if there is any undulation on the surface to be measured, the entire distribution peak collapses, making it impossible to determine the presence or absence of blur (Figure 14 (f), T
h)) However, this is not the case with the measurement optical system shown in Figure 13 (for samples with blur, the peak height is low, and the presence or absence of blur can be determined by the peak height. Ta.

〔Effect of the invention〕

The glossiness measuring device of the present invention is as described above, and includes a first detection means having an extremely high spatial resolution and a second detection means having a detection level matched to the light intensity of the scattered light component. This makes it possible to accurately evaluate the surface properties of the surface to be measured.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating an embodiment of the present invention having a configuration in which a luminous flux is obliquely incident on a surface to be measured and reflected light is received obliquely, and FIG. An explanatory diagram illustrating the configuration when the luminous flux incident on the measurement surface is a parallel luminous flux. Figure (b) explains the configuration when the luminous flux incident on the measured surface is a convergent luminous flux that converges on the measured surface. Explanatory diagram,
Figure 2 (C) is an explanatory diagram illustrating a configuration in which the light flux incident on the surface to be measured is a convergent light flux that is reflected on the surface to be measured and then converged on the detection means. ,
FIG. 2 is a diagram illustrating an embodiment having a configuration in which a light beam is perpendicularly incident on a surface to be measured and reflected light is extracted using a beam splinter, and FIG. An explanatory diagram illustrating the configuration when
is an explanatory diagram illustrating the configuration when the light flux incident on the surface to be measured is a convergent light flux that converges on the surface to be measured, (C1 is a detection means after the light flux incident on the surface to be measured is reflected by the surface to be measured) 3(a) and 3(b) are block diagrams showing an example of the configuration of the processing means used in the present invention, and FIG. 4 is a spatial Explanatory diagram explaining the relationship between resolution and detection means, fifth
The figure is an explanatory diagram explaining the configuration of an example of a conventional glossiness measuring device. Figure 6 is an explanatory diagram explaining an example of the light intensity distribution of reflected light. Figure 7 is an explanatory diagram explaining an example of the light intensity distribution of reflected light. Figure 7 shows the peak intensity and scattered light intensity in reflected light. An explanatory diagram illustrating the configuration of the measurement optical system for investigating the degree of blur on the surface to be measured can be determined from the ratio of Figure 9 is a graph showing the relationship between the ratio of the light intensity of the scattered light component and the image contrast (NSIC*) of each sample, and Figures 10 (a) to (el are the imaging waveforms of each sample). Figure 1) is an explanatory diagram illustrating the configuration of the measurement optical system for investigating the degree of undulation of the surface to be measured from the light intensity distribution of the specularly reflected light component and its neighboring components; Figure 12 (al, (b)
l is the power spectrum sum of the opening angle (θ% in Figure 1) corresponding to 2 of the half-width of the peak obtained with the measurement optical system in Figure 1) and the cross-sectional curve of the undulation of the sample. and a graph showing the relationship between peak shapes, No. 13.
The figure is an explanatory diagram illustrating the configuration of a measurement optical system for investigating the possibility of eliminating the effects of undulation and measuring blur more accurately by using a light beam that converges on the surface to be measured.
1-(h) are graphs showing the results of measuring the light intensity distribution of the sample surface to be measured using the measuring optical system shown in FIG. 13 and the measuring optical system shown in FIG. 1). 1... Surface to be measured 2... Light projecting means 3... Detecting means 4... Optical system 3I... First detecting means 32.
...Second detection means 5...Processing means agent Patent attorney Takehiko Matsumoto pl(e) Figure 10 (e) Figure 1) Figure 12 (a) (b) Figure 13 Figure 14

Claims (1)

[Claims] (1) Light projecting means for generating light directed toward the surface to be measured;
a detection means for receiving and detecting reflected light from the surface to be measured; an optical system for converging the light on the detection means is provided on the path of the light from the light projecting means to the detection means; The glossiness measuring device is configured to measure the glossiness by processing a detection signal from A device comprising a first detection means with high spatial resolution that detects at least a specularly reflected light component, and a second detecting means that has a detection level matched to the light intensity of a component distant from the specularly reflected light component. A glossiness measuring device characterized by: (2) The gloss according to claim 1, wherein the light incident on the surface to be measured is a parallel beam, and the optical system is configured to converge the light reflected by the surface to be measured onto the detection means. Degree measuring device. (3) The light incident on the surface to be measured is a convergent beam that converges on the surface to be measured, and the optical system refocuses the light reflected and dispersed on the surface to be measured onto the detection means. A glossiness measuring device according to claim 1. (4) The glossiness measuring device according to claim 1, wherein the light incident on the surface to be measured is a convergent light beam that is preconverged by an optical system so as to be converged on the detection means. (5) The incident light beam is made to enter the surface to be measured substantially perpendicularly, and the reflected light from the surface to be measured is taken out of the incident light beam by a beam splitter and converged on the detection means. The glossiness measuring device according to any one of the ranges 1 to 4. (6) The spatial resolution of the first detection means is expressed as the angular resolution, and is 0.1°≧tan^-^1 (d/l) [However, in the above formula, d is measured by the first detection means. The minimum possible spatial distance interval, l, represents the distance from the surface to be measured to the first detection means. ], and the detection angle is 1°≧｜tan＾−＾1(r/l)｜≧0° [however,
In the above formula, r represents the spatial distance range that can be measured by the first detection means, and l represents the distance from the surface to be measured to the first detection means. ] The glossiness measuring device according to any one of claims 1 to 5, which is within the scope of the following. (7) The spatial resolution of the second detection means is expressed as the angular resolution, 1°≧tan^-^1(d'/l') [However, in the above formula, d' is The minimum measurable spatial distance interval, l', represents the distance from the surface to be measured to the second detection means. ] within the range of 90°-θ>｜tan＾-＾1(r'/l')｜≧0°
[However, in the above formula, r' represents the spatial distance range that can be measured by the second detection means, l' represents the distance from the surface to be measured to the second detection means, and θ represents the incident angle. ] The glossiness measuring device according to any one of claims 1 to 6, which is within the scope of the following.