Device to measure an embryo's heart in an egg

Abstract

Disclosed is a device for contactless measuring of an embryo's heart rate in an egg whereby infrared light is sent in the egg by one light source, and the reflection of that light is detected by one or more light sensors and converted into a signal representative for the heart rate, whereby a shield is provided to avoid light that is reflected on the egg shell interfering with the light sensors. The shield is provided at the light source and not at the light sensors, whereby a light tube is provided between the light source and the egg and the light tube is internally dimensioned and positioned such that a focused light spot is directed on the egg, and the light tube is dimensioned and positioned such that light reflected on the surface of the egg on the level of the light spot cannot directly reach the light sensors.

Claims

1. Device for measuring of an embryo's heart rate in an egg whereby infrared light is sent in the egg by a light source, and the reflection of that light is detected by one or more light sensors and converted into a signal that is representative for the heart rate, wherein the device comprises the light source whereby a light tube is provided between the light source and the egg, wherein the light tube is internally dimensioned and positioned such that a focused light spot is directed on the egg, and the light tube is dimensioned and positioned such that light reflected on the surface of the egg on the level of the light spot cannot directly reach the light sensors; wherein a length of a light tube is such that the light is directed on the egg in a fine beam; wherein on one end the light tube is provided around the light source so no light can escape, and on the other end the light tube comes close to the egg without making contact with the egg; wherein the light tube is provided with a widened edge at least at the end of the light tube near the egg; and wherein the one or more light sensors are provided around the light source and the light sensors are located in the shadow field of the widened edge of the light tube.

2. Device (1) according to claim 1, wherein the light source (4) can be wholly or partly contained in the light tube (9).

3. Device (1) according to claim 1, wherein the half exit angle of the light source (4) is 3° to 4°.

4. Device (1) according to claim 1, wherein the light tube (9) can be provided with means that bundles the light in a fine beam.

5. Device (1) according to claim 1, wherein the light tube (9) is cylindrical both on the inside and the outside.

6. Device (1) according to claim 1, wherein the light sensors (7) are provided around and in the same plane as the light source (4).

7. Device (1) according to claim 1, wherein the light sensors (7) are located around the light source in a curved surface.

8. Device (1) according to claim 1, wherein three or six light sensors (7) are used.

9. Device (1) according to claim 1, wherein the broadened edge is dimensioned and positioned such that light from the light spot reflected on the surface of the egg cannot directly reach the light sensors.

10. Device (1) according to claim 1, wherein the device (1) comprises means to suppress mechanical vibrations on the light source (4), the light sensors (7) and the eggs (2).

11. Device (1) according to claim 1, comprising measuring means, whereby a tray (3) is provided to hold a matrix of eggs (2) and above the eggs a sensor array (14) is provided per egg comprising a light source (4), light tube (9) and light sensors (7), wherein at least during the measurement, a mechanical shortcut is provided between the tray (3) and the sensor array (14), or between the tray (3) and the measurement means, so as to eliminate vibrations or to vibrate with the same frequency.

12. Device (1) according to claim 1, wherein the mechanical shortcut comprises un upward and/or downward pressure force.

13. Device (1) according to claim 1, wherein the light source (4) consists of an IR LED or a laser beam.

14. Device (1) according to claim 1, wherein the infrared light source (4) emits light with a wavelength in the range between 700 nm and 1100 nm.

15. Device (1) according to claim 1, wherein the device (1) comprises means which keep the luminous intensity of the light source (4) stable.

16. Device (1) according to claim 1, wherein the light sensor (7) is sensitive to the wavelength of the emitted IR light of the light source (4).

17. Device (1) according to claim 1, wherein the device (1) is able to detect very low frequencies, from 0.5 Hz to 7 Hz for a heart rate from 30 to 420 beats per minute.

18. Device (1) according to claim 1, wherein only one focused light source is used.

19. Device (1) according to claim 1, wherein the device is provided with a matrix of eggs (2) whereby the eggs (2) are each provided with their own light source (4), light tube (9) and one or more light sensors (7).

20. Device (1) according to claim 1, wherein both the heart rate and the embryo's movement are measured.

21. Device (1) according to claim 1, wherein the device is provided with means to determine the sample sequence whereby every egg (2) is sampled several times with an interval and per egg (2) a signal is formed with the multiple samples of the egg in question, whereby the variation of the signal shows the viability of an egg.

22. Device (1) according to claim 21, wherein neighbouring eggs (2) are not sampled at the same time.

23. Method for measuring an embryo's heart rate in an egg, by means of a device (1) according to claim 1, comprising the following steps: a. Determining a sample sequence for the simultaneous measuring of non-neighbouring eggs, b. Simultaneously sampling of the eggs of a sample sequence, and subsequently repeating for the eggs of another sequence, c. Repeating step b n times, d. Processing the n signals per egg into a signal varying in time representative for the embryo's heart rate or viability in the egg.

24. Method according to claim 23, whereby in step a sample sequence 1 comprises first selected non-neighbouring eggs in a matrix, sample sequence 2 comprises second selected non-neighbouring eggs in the matrix, sample sequence 3 comprises third selected non-neighbouring eggs in the matrix, and sample sequence 4 comprises fourth selected non-neighbouring eggs in the matrix, and whereby in step b the selected eggs of sample sequence 1, 2, 3 and 4 are scanned in a consecutive time slot.

25. Method according to claim 23, whereby per measurement of the eggs in step b the light source (4) and light sensors (7) of the selected eggs are synchronously switched on and off.

26. Method according to claim 23, whereby the total measurement time for a tray (3) of 150 eggs is 2.5 seconds.

27. Method according to claim 23, whereby there are 256 measurements per egg.

28. Method according to claim 23, whereby during the measurement the light source (4) and light sensors (7), and the eggs (2) are positioned vibrationless.

29. Method according to claim 23, whereby the measurements are not continuous.

30. Method according to claim 23, whereby the measurements are contactless.

31. Method according to claim 23, whereby only one focused light source is used.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) With the intention of better showing the characteristics of the invention, a preferred embodiment of a device to measure an embryo's heart rate in an egg according to the invention is described hereinafter, by way of an example without any limiting nature, with reference to the accompanying drawings wherein:

(2) FIG. 1 schematically shows a preferred embodiment of a device according to the invention whereby the measurement of an embryo's heart rate in one egg is presented;

(3) FIG. 2 shows a preferred embodiment of a device according to the invention whereby a tray of several eggs is scanned;

(4) FIG. 3 shows a preferred embodiment of a vibration free set-up of a device 1 according to the invention;

(5) FIG. 4 shows an example of a matrix of 5 by 5 eggs that are scanned;

(6) FIG. 5 shows a method for the simultaneous scanning/sampling of eggs; and

(7) FIG. 6 shows a time schedule for the scanning/sampling.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(8) FIG. 1 shows a preferred embodiment of a device 1 to measure an embryo's heart rate in an egg 2.

(9) The egg 2 is held on one of its ends or placed in an incubation tray, tray or other support 3. The light source 4, which is centrally positioned above the egg 2, sends infrared light 5 of approximately 850 nm in the other end of the egg 2.

(10) The IR light 5 (see fine arrows) enters the egg 2 and is reflected on a blood vessel 6. Part of this reflected light 5 is detected by one or more light sensors 7.

(11) IR light 5 is also reflected on the surface 8 of the egg 2. To prevent the reflected light 5 from falling directly into a light sensor 7, a light tube 9 is provided around the light source 4. The light tube 9 is provided between the light source 4 and the egg 2. On the side of the egg, the light tube 9 is provided with a broadened edge 10 dimensioned and positioned such that the light directly emitted by the light source 4 and directly reflected on the egg surface 8 is not reflected on the light sensor 7.

(12) Several light sensors 7 are positioned next to the light source 4 in one and the same plane. The more light sensors 7 the better the light is detected that passed through a blood vessel 6 or is reflected on the edge of a blood vessel 6. In certain embodiments three or six light sensors 7 are used.

(13) The light sensors 7 are positioned around the light source 4 and the light tube 9, such that IR light 5 reflected on a blood vessel 6 in the egg 2, can reach one or more light sensors 7. And such that the broadened edge 10 of the light tube 9 prevents IR light 5, directly reflected by the light source 4 on the surface 8 of the egg 2, from reaching a light sensor 7.

(14) On the end of the light tube 9, an infrared filter 11 is optionally provided. In this way IR light with a wavelength >700 nm, for example, can pass through the filter. The filter can be modified so that, for example, only IR light of 850 nm passes through the filter 11.

(15) Preferably, the glass plate 17 has a low infrared absorption. The glass plate 17 can also be provided with a lens to only capture the light from the own light source 4 and not of a neighbouring egg. The glass plate 17 also has a hygienic function such that the glass plate can be easily cleaned.

(16) The part of the device 1 that is located above the glass plate 17 is contained in a casing or sensor array 14. This contains the light source 4, the light tube 9 and the light sensors 7. Preferably, the sensor array 14 is made of infrared light absorbing material such as for example polymethyl methacrylate.

(17) Apart from the contact with the tray 3, there is no contact whatsoever with the egg 2. The measurement is completely contactless. Light source 4, light tube 9 and light sensors 7 make no contact with the egg 2.

(18) The end of the light tube 9 is located approximately 1 cm from the end of the egg 2.

(19) The vertical arrows 12 show the direction of a force with which the device 1 is made vibration free during the measurement. There is a downward force 12 on the casing (sensor array) 14 and an upward force 12 at the bottom of the tray 3, preferably on the steel plate 18 on which the tray 3 is attached and which delimits the bottom of the device.

(20) The force suppresses external vibrations and also results in a vibration shortcut. If there are still vibrations, light sources, light sensors and eggs will vibrate with the same vibration and/or frequency.

(21) FIG. 2 shows a set-up that comprises several devices 1 according to FIG. 1. For example, a tray can contain 150 eggs in a matrix/array. Above every egg a device 1 is provided with its own light source 4, light tube 9 and light sensors 7. FIG. 2 shows one row of the matrix/array. Light source 4, light tube 9 and light sensors 7 are therefore also provided in a matrix/array (not shown in the figure).

(22) FIG. 3 shows a lateral view of a vibration free set-up of a device 1 according to the invention. Preferably, the eggs 2 are in a grid of x by y eggs. The tray 3 with eggs 2 is supplied via a conveyor belt 13 and placed under the array 14 with light sources 4 and light sensors 7. The array 14 contains one light source 4 per egg and several light sensors 7 per egg.

(23) Preferably, the array 14 can be lifted up to position the incubation tray, tray, or other support 3 with eggs 2. The array 14 is completely loose and free of the eggs, such that no contact is made with the eggs at any time.

(24) During the measurement the set-up is made vibration free to exclude mechanical vibration between the array 14 and the eggs 2. Vibrations are very disadvantageous for the precise measurement of an embryo's heart rate in an egg. Indeed, the signal of the heart rate is very weak compared to possible interference by vibrations.

(25) Preferably, in a vibration free set-up the array 14 with light sources 4 and light sensors 7, the tray 3 with eggs 2 and possibly the conveyor belt 13, at least during the measurement, are kept in place by an appropriate construction. A plate 15 has been provided under the conveyor belt 13 to support the tray 3 when it is pressed against the plate 15, and to make it vibration free. The entire unit is supported on dampers 16. An extra plate 17 is provided to support the conveyor belt 13 and the tray 3. The construction can be provided with a heavy block 20 at the bottom, for example concrete. Consequently, a very rigid and vibration free construction is created, at least during the measurement.

(26) FIG. 4 shows a scan of an array of 5 by 5 eggs. The shaded eggs cannot be scanned simultaneously with the non-shaded eggs, in other words, neighbouring eggs are not scanned simultaneously. Around every egg that is scanned at a particular moment in time, there is a barrier of non-scanned eggs (shaded). In this way, every egg 2 in the tray is surrounded by 8 eggs (see frame) that will not be scanned at the same moment that the egg in question is scanned. The shaded eggs then serve as shielding or barrier for the light that measures the non-shaded egg. The other eggs 2 (not shaded) can be scanned in the same time slot.

(27) The eggs are scanned in matrix patterns of n by n eggs. This means every egg that is scanned at a certain time is surrounded by n.sup.2−1 eggs. In the example of a scan matrix of 3 by 3, 1 egg is therefore surrounded by 8 eggs.

(28) In a scan matrix of 3 by 3 for example, the time is divided into 9 time slots. In time slot 1, egg 1 is measured for example, in time slot 2 egg 2, and in time slot 3 egg 3, etc. Whereby egg 1 does not necessarily have to lie next to egg 2 and egg 2 does not necessarily have to lie next to egg 3.

(29) Such method of scanning avoids interference with the heart rate of embryos of neighbouring eggs during the measurement.

(30) FIG. 5 shows a method for the simultaneous scanning of eggs. During scan 1 the eggs with number 1 are scanned, during scan 2 the eggs with number 2, during scan 3 the eggs with number 3, and during scan 4 the eggs with number 4. In this way an optimum number of non-neighbouring eggs are scanned at the same time.

(31) The scan speed is sufficiently high such that a quick measurement is obtained, even if not all the eggs of the tray are measured at the same time.

(32) FIG. 6 shows a time schedule for the scan. The eggs numbered 1, 2, 3 and 4 are scanned after each other in a subsequent time frame or time slot. This is repeated n times, e.g. 256 times. Thus, every egg is measured n times in a different time slot. The total measurement time for a tray of eggs is about 2.5 seconds and about 256 measurements per egg. For a tray of 150 eggs, the total amount of measurements per tray is 256×150=38.400.

(33) During the measuring the tray is kept under a pressure force to prevent that the eggs vibrate.

(34) The n signals of every egg are processed into a signal that varies in time that is representative for an embryo's heart rate in the egg in question.

(35) Unlike other systems the measurement is not continuous.

(36) Every time a scan or sample is taken of a particular egg, or a certain position, the light source is switched on and off and practically synchronously or simultaneously with this the light sensors too. The necessary electronics means and algorithms are applied for this.

(37) The present invention is by no means limited to the embodiments described as an example and shown in the drawings, but a device to measure the heart rate of an embryo in an egg according to the invention as defined by the claims can be realised in all kinds of variants without departing from the scope of the invention.