JP2000241347A - Method and apparatus for examining egg - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an egg inspecting method capable of detecting an abnormal egg with high accuracy regardless of a size of an egg and an apparatus adapted to this method. SOLUTION: A normalization part 2 divides a first signal given through a first band-pass filter 31 permitting a wavelength large in absorption due to internal abnormality t pass, by a second signal given through a second ban- pass filter 32 permitting a wavelength different in absorption due to the color of a egg shell to pass, and also divides a third signal given through a third band-pass filter 33 permitting a wavelength small in absorption due to internal abnormality to pass by the second signal to apply the division result to a differential calculation part 3. The differential calculation part 3 calculates the difference between both of them to apply the same to a decision part 4, and the decision part 4 compares the given difference with a threshold and decides an abnormal egg in the case of being the threshold or more to output a signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for non-destructively inspecting an egg for internal abnormalities and an apparatus used for carrying out the method.

[0002]

2. Description of the Related Art Eggs produced in a poultry farm include abnormal eggs such as blood spot eggs in which small clots are mixed in the eggshell, and eggs mixed with meat spots in which meat substances are suspended in egg white or entangled in karaza. In order to ship normal eggs to be eaten, non-destructive inspection is performed to determine whether or not a plurality of collected eggs are abnormal eggs.

In order to non-destructively inspect an egg, an inspector holds the egg over light emitted from a light source such as a fluorescent lamp and visually judges whether or not the egg is abnormal. However, while such an inspection requires a skilled inspector, there is a problem that even an experienced inspector cannot perform inspection work for a long time.

[0004] Therefore, Japanese Patent Publication No. 56-735 discloses the following egg testing apparatus. Light is emitted to the egg by the light emitting device, and the transmitted light is received by the light receiving device. The light receiving device is provided with two phototransistors that output an electric signal according to the intensity of the received light. An optical filter transmitting light having a wavelength of 575 nm is provided in the light receiving portion of one phototransistor, and an optical filter transmitting light having a wavelength of 590 nm is provided in the light receiving portion of the other phototransistor. The transmitted light is incident on the corresponding phototransistor through both optical filters, respectively.
There, photoelectric conversion is performed.

[0005] The first signal output from one phototransistor and the second signal output from the other phototransistor are provided to an arithmetic unit. The arithmetic unit is the first
The first signal is normalized by dividing the signal by the second signal. If the level of the normalized signal is equal to or less than a predetermined level, it is determined that the egg is a blood spot egg.

[0006] As described above, the intensity of the transmitted light of 575 nm absorbed by the blood clot is normalized by the intensity of the transmitted light of 590 nm that changes depending on the color of the eggshell, such as white or brown, so that the influence of the color of the eggshell is reduced. can do.

[0007]

[Problems to be solved by the invention]
In the egg test apparatus disclosed in JP-A-56-735, as described above, when the level of the normalized signal is equal to or lower than a predetermined level, it is determined that the egg is a bloody egg, so that a minute clot is formed. If they are mixed, the level of the normalized signal is not so low, and there is a risk of overlooking this. 575n
Since the intensity of the transmitted light of m also changes depending on the size of the egg (transmitted light path length) and the shade of the color of the eggshell, there is also a problem that the accuracy of abnormal egg detection is low.

The present invention has been made in view of the above circumstances, and has as its object to use the transmitted light of an egg to obtain an intensity of a first wavelength which is largely absorbed by an internal abnormality of the egg.
Measure the intensity of the second wavelength where absorption differs depending on the type of eggshell, and the intensity of the third wavelength where absorption due to internal abnormalities is small,
The obtained intensity of the third wavelength and the intensity of the first wavelength are normalized by the intensity of the second wavelength, respectively, and the difference between the normalized intensity of the first wavelength and the intensity of the third wavelength is calculated. By determining whether the egg is internal abnormal or not based on the size of the egg and the color of the eggshell,
An object of the present invention is to provide an egg test method capable of detecting an abnormal egg with high accuracy, and an apparatus used for carrying out the method.

[0009]

According to a first aspect of the present invention, there is provided a method for detecting an egg, wherein the egg is irradiated with light having a required wavelength from a light source to obtain transmitted light, and the transmitted light is used to absorb the egg due to an internal abnormality of the egg. The intensity of the first wavelength is large, and the intensity of the second wavelength, the absorption of which differs depending on the type of the eggshell, is measured. Based on the obtained intensity of the first wavelength and the intensity of the second wavelength, the internal abnormality of the egg is determined. In the egg detection method for detecting, the transmitted light is used to measure the intensity of the third wavelength having a small absorption due to the internal abnormality, and the obtained intensity of the third wavelength and the intensity of the first wavelength are converted to the second wavelength. And a difference between the normalized first and third wavelength intensities is calculated, and it is determined whether the egg has an internal abnormality based on the obtained difference. And

[0010] The egg inspection apparatus according to the second invention is a measuring section for measuring the intensity of the first wavelength included in the transmitted light obtained by irradiating the egg with light having a required wavelength and having a large absorption due to an internal abnormality of the egg. And a measurement unit that measures the intensity of the second wavelength having different absorption depending on the type of the eggshell using the transmitted light, and the inside of the egg based on the obtained intensity of the first wavelength and the intensity of the second wavelength. In an egg inspection apparatus including a detector that detects an abnormality,
A measuring unit that measures an intensity of a third wavelength having a small absorption due to the internal abnormality using the transmitted light; and the detector normalizes the third intensity and the first intensity by the second intensity, respectively. And means for calculating the difference between the normalized first and third intensities.

[0011] The egg is irradiated with light containing a required wavelength from a light source such as a lamp or natural light to obtain transmitted light, and the transmitted light is used to obtain an intensity of a first wavelength, which is greatly absorbed by an abnormality inside the egg.
The intensity of the second wavelength having different absorption depending on the type of eggshell and the intensity of the third wavelength having small absorption due to the internal abnormality are measured.

FIG. 2 is a graph showing the absorption spectrum of blood and the coefficient of variation of the transmittance of a plurality of eggs. In the figure, the left vertical axis represents the absorbance, and the right vertical axis represents the variation coefficient of the light transmittance (standard). Deviation / average value), and the horizontal axis represents wavelength. In the figure, line a shows the absorption spectrum of blood, and line b shows the variation coefficient of light transmittance for a plurality of wavelengths.

As is apparent from the line a shown in FIG. 2, the blood absorbance has a maximum value near 540 nm and 575 nm, and a minimum value near 560 nm, and the blood absorbance at a wavelength longer than 610 nm. There is almost no absorption. Further, as is clear from the b-line, the coefficient of variation of the light transmittance of a plurality of eggs having different shades and sizes of color is large at 645 nm, where there is almost no absorption by blood.

Therefore, when the internal abnormality is a blood clot, the above-mentioned second wavelength is set to around 645 nm and the third wavelength is set to 560 nm.
nm. Further, the first wavelength has a high detection sensitivity 5.
It is set to around 75 nm.

The intensity of the first to third wavelengths may be measured by dispersing the transmitted light and measuring the intensity of each wavelength. Alternatively, the transmitted light may be incident on an optical filter that transmits each wavelength, The light intensity may be measured.

The intensity of the third wavelength and the intensity of the first wavelength obtained in this way are normalized by, for example, respectively dividing by the intensity of the second wavelength, and the normalized intensity of the first wavelength and the intensity of the third wavelength are respectively divided. The difference between the wavelength intensities is calculated, and if the obtained difference is smaller than a preset value, it is determined that the egg is abnormal.

As described above, the intensity of the first wavelength at which absorption due to the internal abnormality is large, and the intensity of the third wavelength at which absorption due to the internal abnormality is small
In order to normalize the intensity of the wavelength by the intensity of the second wavelength, the absorption of which depends on the size of the egg and the shade of the eggshell,
The effects of egg size and shade of eggshell color can be reduced. Furthermore, in order to obtain the difference between the normalized intensity of the first wavelength and the intensity of the third wavelength, the influence of the size of the egg and the shade of the color of the eggshell can be further reduced, and the presence or absence of an internal abnormality can be accurately determined. Wear. Thereby, regardless of the shade of the color of the eggshell and the size of the egg, a minute internal abnormality can be detected, and the abnormal egg can be detected with high accuracy.

[0018]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of an egg test apparatus according to the present invention. In the figure, reference numeral 6 denotes a light source such as a halogen lamp that emits light having a wavelength of 500 nm to 700 nm. A reflector 7 is disposed at a predetermined distance from the light source 6, and the light emitted from the light source 6 and the light reflected by the reflector 7 are transmitted through the first lens 11.
Is incident on. The first lens 11 converts the incident light into parallel light having substantially the same cross-sectional area as the cross-sectional area of the egg E.
The light exits to the second lens 12 disposed to face the lens.

An egg E is provided between the first lens 11 and the second lens 12.
Is disposed, and the transmitted light transmitted through the egg E is transmitted through the second lens 12.
The light is focused. In the optical path of the light emitted from the second lens 12, first and second half mirrors 21 and 22 are arranged at an appropriate distance from each other and at a predetermined angle with respect to the optical path. The light reflected by the mirror 21 passes through the first band-pass filter 31 that passes light having a wavelength near 575 nm, which is largely absorbed by the blood clot, for example.
The light enters the photoelectric converter 41.

The light passing through the first half mirror 21 and reflected by the second half mirror 22 passes light having a wavelength of about 645 nm, whose absorption varies depending on the color of the eggshell.
The light incident on the second photoelectric converter 42 via the band-pass filter 32 and passing through the first half mirror 21 and the second half mirror 22 passes light having a wavelength of about 560 nm, which is less absorbed by the blood clot. The light enters the third photoelectric converter 43 via the three-bandpass filter 33.

The first half mirror 21 and the second half mirror 22 have the intensity of the light reflected by the first half mirror 21 and the light reflected by the second half mirror 22 after passing through the first half mirror 21. And the intensities of the light passing through the first half mirror 21 and the second half mirror 22 have the same value.

The first to third photoelectric converters 41 to 43 convert the incident light into electric signals corresponding to the intensity of the incident light, and convert the obtained electric signals via analog / digital converters 9, 9 and 9, It is given to the normalization unit 2 of the arithmetic unit 1, respectively. Normalization unit 2
Converts the first signal provided from the first photoelectric converter 41 into the second signal
By dividing by the second signal given from the photoelectric converter 42 and dividing the third signal given from the third photoelectric converter 43 by the second signal, the eggshell is obtained from the first signal and the third signal. Normalization processing for removing the influence is performed, and the normalized first signal and third signal are given to the difference calculation unit 3.

The difference calculation section 3 calculates the difference between the third signal and the first signal by subtracting the first signal from the third signal, and supplies the difference to the determination section 4.
In the determination unit 4, a threshold value for determining the quality of the egg is set in advance, and the determination unit 4 compares the given difference with the threshold value. If the difference is equal to or less than the threshold value, the determination unit 4 determines that the egg is abnormal and outputs a signal. Is output.

In the present embodiment, the egg E is obtained by using the first signal obtained through the first band-pass filter 31 that passes light having a wavelength of about 575 nm, which is largely absorbed by the blood clot.
However, the present invention is not limited to this, and instead of or in addition to the first signal, light having a wavelength corresponding to other internal abnormalities such as meat substance or egg white turbidity is used. The egg E may be inspected using a signal obtained through a band-pass filter that passes through the egg E. In this case, the obtained signal is normalized using the above-described second signal, and the normalized signal and the normalized third signal or the light of another wavelength whose absorption due to the internal abnormality is small are photoelectrically converted, Find the difference from the normalized signal. Thereby, regardless of the type of the eggshell and the size of the egg, a minute internal abnormality can be detected, and the abnormal egg can be inspected with high accuracy.

[0025]

Next, the results of a comparative test will be described. FIG. 4 is a graph showing the results of inspection of normal eggs and abnormal eggs mixed with blood clots using the apparatus disclosed in Japanese Patent Publication No. 56-735, with the vertical axis representing the first signal normalized by the second signal.
The signal level is shown. In this case, the first signal is 5
Obtained using an optical filter that passes light of 75 nm,
The signal was obtained using an optical filter transmitting 590 nm light.

FIG. 5 is a graph showing the results of inspection of normal eggs and abnormal eggs mixed with blood clots by a conventional apparatus in which the passing wavelength of an optical filter for obtaining the second signal is changed. In this case, the first signal is obtained using an optical filter that passes light of 575 nm, and the second signal is
Obtained using an optical filter that transmits light of nm.

On the other hand, FIG. 3 is a graph showing the results of inspection of normal eggs and abnormal eggs mixed with blood clots by the apparatus of the present invention. The vertical axis represents the first signal and the second signal normalized by the second signal. The level of difference from the normalized third signal is shown.
In the apparatus of the present invention, a first signal is obtained by using an optical filter that transmits light of 575 nm, a second signal is obtained by using an optical filter that transmits light of 645 nm, and an optical filter that transmits light of 560 nm is obtained. A third signal was obtained.

As is clear from FIGS. 4 and 5, in the conventional apparatus, a part of the test result of the normal egg and one of the test results of the abnormal egg are obtained regardless of the passing wavelength of the optical filter for obtaining the second signal. This causes false detection or overlooking of abnormal eggs. On the other hand, as is clear from FIG. 3, in the apparatus of the present invention, the test result of the normal egg and the test result of the abnormal egg do not overlap, and for example, by setting the threshold value to 0.10. It can be detected with high accuracy.

[0029]

As described in detail above, in the present invention,
The present invention has excellent effects, such as being able to detect minute internal abnormalities regardless of the type of eggshell and the size of the eggs and to inspect the quality of the eggs with high accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an egg inspection apparatus according to the present invention.

FIG. 2 is a graph showing an absorption spectrum of blood and a coefficient of variation of transmittance of a plurality of eggs.

FIG. 3 is a graph showing a result of inspection of a normal egg and an abnormal egg mixed with a blood clot by the device of the present invention.

FIG. 4 is a graph showing the results of inspection of normal eggs and abnormal eggs mixed with blood clots using the apparatus disclosed in Japanese Patent Publication No. 56-735.

FIG. 5 is a graph showing a result of examining a normal egg and an abnormal egg mixed with a blood clot by a conventional device in which a passing wavelength of an optical filter for obtaining a second signal is changed.

[Explanation of symbols]

 Reference Signs List 1 arithmetic unit 2 normalization unit 3 difference calculation unit 4 determination unit 6 light source 21 first half mirror 22 second half mirror 31 first bandpass filter 32 second bandpass filter 33 third bandpass filter 41 first photoelectric converter 42 2nd photoelectric converter 43 3rd photoelectric converter

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G051 AA90 AB20 BA20 CA07 CB02 CC07 EA08 EA12 EB01 EB02 EC03 2G059 AA05 BB11 CC20 DD13 EE01 FF06 GG10 HH02 HH06 JJ03 JJ11 JJ14 JJ22 KK03 MM01 MM05 MM09

Claims (2)

[Claims] An egg is illuminated with light having a required wavelength from a light source to obtain transmitted light, and the transmitted light is used to determine the intensity of the first wavelength, which is largely absorbed by an internal abnormality of the egg, and the type of the eggshell. The intensity of the second wavelength having different absorption is measured,
In the egg detection method for detecting an internal abnormality of an egg based on the obtained intensity of the first wavelength and the intensity of the second wavelength, the intensity of the third wavelength having a small absorption due to the internal abnormality is reduced using the transmitted light. Measured, the intensity of the obtained third wavelength and the intensity of the first wavelength are normalized by the intensity of the second wavelength, respectively, and the difference between the normalized intensity of the first wavelength and the intensity of the third wavelength is calculated. An egg inspection method comprising: determining whether the egg has an internal abnormality based on the obtained difference. 2. A measuring unit for measuring an intensity of a first wavelength included in transmitted light obtained by irradiating an egg with light having a required wavelength and having a large absorption due to an internal abnormality of the egg, and using the transmitted light. A measuring unit that measures the intensity of the second wavelength having different absorption depending on the type of the eggshell, and a detector that detects an internal abnormality of the egg based on the obtained intensity of the first wavelength and the intensity of the second wavelength. An egg test apparatus comprising: a measuring unit configured to measure, using the transmitted light, an intensity of a third wavelength having a small absorption due to the internal abnormality, wherein the detector measures the third intensity and the first intensity by the second intensity. An egg inspection apparatus, comprising: means for normalizing each of the two intensities; and means for calculating a difference between the normalized first and third intensities.