JP2007111315A - Method and device for detecting pupil using two kinds of light sources - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and method for securely detecting pupils by improving the quality and disposition of light sources. <P>SOLUTION: The face surface including the pupils are irradiated with two kinds of light sources from a camera means side: a first illumination light source for capturing bright pupils and a second illumination light source for capturing dark pupils. The light sources are disposed in such a way that the light from the first illumination light source is emitted from within an opening part of a common light axis as seen from the face surface side and that the light from the second illumination light source is emitted from the position close to or circumscribed to the outer periphery of the opening part of the common light axis. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is a technique for detecting a remote pupil using a CCD camera or the like. By utilizing both the difference in the position of the light source and the difference in the amount of retinal reflection due to the difference in the wavelength of the light source, the position of the pupil is determined. The present invention relates to a pupil detection device and method for detection.

  The pupil itself is small and not only looks like a circle or an ellipse when viewed from any direction, but unlike the black eye, it is difficult to hide in the eyelid, so it is a feature point for measuring the posture of the head It's being used. Utilizing this, the “pupil mouse” makes the amount of movement of the pupil correspond to the movement of the cursor on the personal computer screen, and an application relating to a technique that can move the cursor by the movement of the head has been made (patent) Document 1 (Japanese Patent Laid-Open No. 2005-182247).

In Non-Patent Document 1, in order to detect a pupil stably and with high accuracy, two light sources having the same wavelength that are different from each other in the installation position are alternately turned on, and a bright image (bright pupil image) and a dark image are generated from the resulting pupil. A technique for making it easy to detect a pupil by obtaining an image (dark pupil image) and subtracting them is disclosed. In order to obtain a bright pupil image, it is necessary to install a light source on or near the optical axis of the camera, and in order to obtain a dark pupil image, it is necessary to install a light source away from the optical axis of the camera. In the method of this document, these two light sources are synchronized with the odd field and the even field of the video camera, alternately turned on, and a bright pupil image and a dark pupil image are obtained alternately, and an image difference is performed. The background part other than the pupil is canceled out, and only the pupil part is highlighted to make it easy to detect the pupil. However, the effect depends on how far away the light source is from the optical axis of the camera and how far away it is. To maximize the effect, it is far away from the optical axis. Therefore, the overall apparatus tends to be large, resulting in lack of versatility.
Furthermore, dispersively arranging the light sources located away from the optical axis makes it easy for the light source to be reflected as spectacle reflection, which is also a major problem in pupil detection.

Furthermore, Patent Document 2 (Japanese Patent No. 2988235) discloses a light source (non-coaxial illumination) in each of the left and right positions greatly deviated from the optical axis, in addition to the light source (coaxial illumination) on the optical axis of the camera. ) Is presented. According to this method, when the bright pupil image and the dark pupil image are differentiated, the corneal reflection image of the coaxial illumination of the camera and the corneal reflection of the non-coaxial illumination do not cancel each other. Can be detected, and its corneal reflection is useful for detecting the line-of-sight direction.
However, if the coaxial illumination and the non-coaxial illumination are separated from each other in this way, the reflected images of the glasses do not cancel each other, so that a noise image due to the reflected glasses appears and is difficult to remove. is there.

  Patent Document 3 (Japanese Patent Laid-Open No. 2004-261598) relating to an application by Agilent Technologies obtains a dark pupil image by arranging one of light sources having different wavelengths at a position close to the optical axis of the camera in order to obtain a bright pupil image. Therefore, a configuration is disclosed in which the other is disposed at a position away from the optical axis of the camera. This document describes a method in which these light sources are turned on almost simultaneously, wavelength separation is performed by an optical system, a bright pupil image and a dark pupil image are obtained, and a difference between them is extracted to extract a pupil image. The reason why the two wavelengths are used here is to simultaneously obtain a bright pupil image and a dark pupil image, and there is no suggestion which of the two wavelengths should be close to the optical axis. Note that at the end of paragraph (0035) of this document, “When measured with a conventional silicon-based detector, the retinal return signal is generally stronger at 800 nm than at a wavelength of 950 nm. It is desirable to associate the shorter wavelength with the on-axis light source. " However, this is a description relating to the sensitivity of the camera, and if the sensitivity of the camera is high, the image of the portion other than the pupil will also become bright, and thus there is no effect on the ease of pupil detection by image difference.

Further, Patent Document 4 (Japanese Patent Laid-Open No. 2-224737) discloses a method in which LEDs having different wavelengths are arranged in a double ring shape, a bright pupil image is obtained when the inner ring is turned on, and the outer ring is turned on. A method for obtaining a dark pupil image is proposed.
As in the case of the above-mentioned Patent Document 3 (Japanese Patent Application Laid-Open No. 2004-261598), this document is used to separate images obtained by simply different wavelengths based on the difference in wavelength, and is used in the present invention described later. The “difference of the amount of retinal reflection depending on the wavelength” is not considered.

  The invention described in Patent Document 5 (Japanese Patent Application No. 2005-241728) according to the proposal of the present inventors is a method of emitting light of two wavelengths from the opening of a camera. In this case, since light of two wavelengths is mixed and emitted using a branching fiber, it is possible to have light having the same luminance profile for each light source of two wavelengths, and both wavelengths in each part of the face. Since almost the same luminance distribution can be obtained by the above, it is possible to cancel out brilliantly, and it is advantageous in pupil detection in that corneal reflection and spectacle reflection are also easily canceled by the difference.

  However, since the corneal reflection disappears, it is difficult to use in applications that detect corneal reflection such as eye gaze detection. In addition, when it is necessary to obtain the center position of the eyeball and the center of the corneal sphere, the same can be said because it is necessary to detect the corneal reflection image. Also, the difference in pupil luminance between, for example, an LED with a center wavelength of 850 nm and an LED with a wavelength of 950 nm for the purpose of pupil detection only is not very large. Especially in an environment where the surroundings are very bright, in order to prevent the pupil image itself from being saturated in the camera image, it is possible to reduce the aperture, reduce the amplifier gain, shorten the shutter speed, etc. All of them are almost equivalent to lowering the gain, and the luminance of the pupil image of the difference image is lowered, so that pupil detection becomes difficult. Therefore, there is a need for a method that strongly exerts the effect of the bright pupil and the dark pupil, not only from the difference in wavelength.

The invention described in Patent Document 6 (Japanese Translation of PCT International Publication No. 2002-513176) utilizes the fact that the reflectance of two wavelengths is the same on the face and the surface of the eye, but is different on the retina. And in common. However, this is a configuration in which LEDs of two types of wavelengths are arranged in a ring shape around the opening of the camera (the LEDs of two types of wavelengths are arranged at the same distance from the optical axis of the camera), which is different from the configuration of the present invention. .
JP 2005-182247 A Japanese Patent No. 2988235 JP2004-261598 JP-A-2-224737 Japanese Patent Application No. 2005-241728 Special table 2002-513176 "Pupil detection and tracking using multiple light sources", author H. Morimoto et al. (CH Morimoto, D. Koons, A. Amir, M. Flickner), Image and Vision Computing 18 (2000) 331-335 (Image and Vision Computing 18 (2000) 331-335)

As a technique having an important relationship with the above-described pupil detection, there is a corneal reflection measurement technique, which can be used for posture or line of sight detection in connection with or independently of pupil detection. All of the three patent documents described below relate to the invention of the present inventor, and are related to corneal reflection and are used for detecting the line of sight. The invention described in Patent Literature 7 discloses a gaze detection method and gaze detection device, the invention described in Patent Literature 8 discloses a three-dimensional viewpoint measurement device, and the invention according to Patent Literature 9 discloses a gaze detection device using a distance image sensor. Although the position of the cornea is closely related to the position of the camera and the light source, these inventions do not analyze the light source in relation to the bright and dark pupil illumination.
JP-A-2005-185431 JP 2005-198743 A JP2005-230049

The main object of the present invention is to detect pupils by improving the quality and arrangement of light sources in a pupil detection device that detects images by illuminating the face including the pupils with two types of light sources from the camera means side. It is an object of the present invention to provide a pupil detection device that ensures the above.
Another object of the present invention is to provide a pupil detection method capable of reliably performing pupil detection.
Still another practical object of the present invention is to improve the reliability of the detection results of the above-described apparatus and method, and to enable removal of noisy reflections caused by high brightness, which could be a conventional obstacle, Similarly, corneal reflection caused by high luminance is made possible simultaneously with pupil detection.

In order to achieve the above object, a pupil detection device according to claim 1 according to the present invention comprises:
A camera means, a light source, an optical path forming means, and a computing means. By the optical path forming means, the subject is irradiated with the face from the camera means side by the light source, and an image of the face including the pupil is connected to the camera means. A pupil detection device that is arranged while maintaining an imaged relationship and calculates the imaged data to detect the pupil,
The light source is
A first illumination light source including a first wavelength component in which the reflection in the pupil of the subject becomes a bright pupil;
The subject's intra-pupil reflection includes a second wavelength component that becomes a dark pupil, and other than the pupil includes a second illumination light source that exhibits an illumination effect equivalent to that of the first illumination light source. The intensity ratio between the intensity and the second illumination light source is kept constant,
The camera means is
First image data acquisition means by the first illumination light source;
Second image data acquisition means by the second illumination light source,
The optical path forming means includes
The first image data acquisition means and the second image data acquisition means of the camera means are opposed to the face with a common optical axis,
The position where the light from the first illumination light source is emitted from the opening of the common optical axis when viewed from the face side, and the light from the second illumination light source is close to the outer periphery of the opening of the common optical axis Arranged to fire from,
The computing means is means for computing a pupil of the first image data and the second image data.

The pupil detection device according to claim 2 of the present invention is the pupil detection device according to claim 1,
The first illumination light source is configured to combine the light emission of a plurality of light emitting elements for short wavelengths by the optical path forming unit and emit the light from the opening of the common optical axis through an irradiation angle adjusting optical unit. Has been.
The pupil detection device according to claim 3 of the present invention is the pupil detection device according to claim 2,
The second illumination light source emits light emitted from one or more long-wavelength light emitting elements disposed on the outer periphery of the irradiation angle adjusting optical unit from outside the opening of the common optical axis by the optical path forming unit. It is configured as follows.
The pupil detection device according to claim 4 of the present invention is the pupil detection device according to claim 2,
Light from the first and second illumination light sources is configured to be coupled via a light splitting unit, a half mirror, and the like disposed on the common optical axis.
The pupil detection device according to claim 5 of the present invention is the pupil detection device according to claim 2,
The second illumination light source is configured to emit light emitted from a plurality of light emitting elements for long wavelengths directly provided outside the opening of the common optical axis from outside the opening of the common optical axis. .
The pupil detection device according to claim 6 of the present invention is the pupil detection device according to claim 1,
The first and second illumination light sources include a plurality of short-wavelength light-emitting elements and light emitted from one or more long-wavelength light-emitting elements arranged outside the light-emitting elements on the common optical axis. It is configured to be coupled via a dividing means, a half mirror or the like.

The pupil detection method according to claim 7 according to the present invention comprises:
A first illumination light source including a first wavelength component that generates a bright pupil image;
A second illumination light source having a second wavelength component that generates a dark pupil image and having an intensity equivalent to that of the first illumination light source except for the pupil;
First and second imaging means for capturing an illumination image from each of the light sources, the optical systems being substantially the same and arranged on a common optical axis,
Position of the first illumination light source close to the outer periphery of the opening having a common optical axis relationship from within the openings of the first and second imaging means having a common optical axis relationship. An arrangement step of arranging so that illumination light is emitted from,
A first illumination step of activating and illuminating the first illumination light source;
A second illumination step of activating and illuminating the second illumination light source;
A data acquisition step of capturing the respective illumination images under the respective illuminations to acquire first image data and second image data;
A calculation step of detecting a pupil by performing a difference calculation process on the first image data and the second image data.

According to the device and method of the present invention, the pupil and corneal reflection can be easily detected regardless of the small size as compared with the conventional similar device and method.
While the same wavelengths are arranged in a double ring shape with the same size, the pupil and corneal reflection can be detected robustly even when the usage environment is bright.
Further, the image processing is also easy for the case of wearing glasses, and even when wearing glasses, the pupil can be detected without erroneously judging the eye light reflection as the pupil.
By separating the two wavelengths, it is possible to make the two-wavelength light sources instantaneously lit at the same time, thereby making them stronger against vibration. Detection of a corneal reflection point (region) is possible simultaneously with pupil detection.

The principle of the present invention is to prepare two types of short wavelength (for example, 850 nm) and long wavelength (for example, 950 nm) as a light source for illumination, and arrange their arrangement with a common optical axis and lens aperture of two cameras using an image sensor. Determine the relationship.
Thus, pupil detection is performed by reliably acquiring bright pupil image data with a short wavelength and dark pupil image data with a long wavelength. By disposing a long-wavelength light source close to the opening, generation of undesirable noise light is prevented.

(First embodiment of pupil detection)
FIG. 1 is an optical path diagram showing a first embodiment of a pupil detection device according to the present invention.
In the figure, the objective lens 9, the lens 8, the short wavelength bandpass filter 5, the lens 3, and the short wavelength image sensor 1 form the main part of the first camera.
The objective lens 9, the lens 8, the long wavelength bandpass filter 6, the lens 4, and the long wavelength image sensor 2 form a main part of the second camera.
A half mirror (or dichroic mirror) 7 is disposed on the optical axes of these two cameras, and the two cameras share an optical axis in appearance.
A half mirror 10 for coupling an illumination light source is provided on the object side of the objective lens 9.

  The short wavelength light source (inside the opening) 21 is composed of short wavelength light emitting elements 21a to 21d, and is connected to the coupling portion 24 by branch fibers 23a to 23d. An irradiation angle adjusting lens 25 is disposed in front of the coupling portion 24. Around the irradiation angle adjusting lens 25, a plurality of long wavelength light emitting elements 26a to form a long wavelength light source 26 are arranged. The number of the long wavelength light emitting elements 26a is adjusted in relation to the short wavelength light source. In the figure, a view of the irradiation angle adjusting lens 25 and the long wavelength light emitting element 26n from the direction of the arrow shown in the front view is enlarged and shown as a front view. In this example, 14 long-wavelength light-emitting elements 26a˜ are arranged, 14 long-wavelength light-emitting elements 26j˜ are arranged, and 4 long-wavelength light-emitting elements 26k˜ are arranged in a cross. These three examples are shown.

  When the short wavelength light source and the long wavelength light source are activated at the same time, each illumination light is reflected by the half mirror 10 and irradiates the face. At this time, when viewed from the face, the light of the short wavelength light source is irradiated from within the aperture including the common optical axis of the camera, and the light of the long wavelength light source is circumscribed in the aperture away from the common optical axis of the camera. It will be irradiated from the position to do. The face image including the bright pupil image and the face image including the dark pupil image by the illumination are transmitted through the half mirror 10 and the lenses 9 and 8, separated by the half mirror 7, and short wavelength (850 nm). ) Passes through the band-pass filter 5 and is imaged on the short-wavelength image sensor 1 by the lens 3. The light including the long wavelength (950 nm) transmitted through the half mirror 10 and reflected and separated by the half mirror 7 is transmitted through the band pass filter 6 and is imaged on the long wavelength image sensor 2 by the lens 4.

The outputs of the image sensors 1 and 2 are subjected to a difference calculation for each pixel by an arithmetic circuit (not shown), and a pupil image is detected. The principle of this state and simultaneous cornea detection will be described with reference to FIG. FIG. 4 is a diagram showing one scanning line that forms a differential image of the outputs of the image sensors 1 and 2.
The level of the bright pupil imaged on the short wavelength image sensor 1 is higher than the surrounding portion, and the level of corneal reflection is higher. The level of the dark pupil imaged on the long wavelength image sensor 2 is smaller than the level of the bright pupil, and the region is substantially equal to the region of the bright pupil. The center of corneal reflection on the long-wavelength image sensor 2 coincides with that of the bright pupil, the corneal reflection region is wider than the corneal reflection region of the bright pupil, and the level of reflection is lower than that of the bright pupil. As a result of the difference, a scanning waveform shown in FIG. 4 is obtained.
That is, the corneal reflection is not offset by the difference between the bright pupil image and the dark pupil image because the positions of the short wavelength light source and the long wavelength light source are different. As a result, in FIG. 4, it remains in the difference image as a high luminance part (corneal reflection by the short wavelength light source) and a low luminance part (corneal reflection by the long wavelength light source).
As can be understood from FIG. 4, it is easier to set the threshold value by detecting from the difference image than by detecting the corneal reflection from the bright pupil image or the dark pupil image. This increases the robustness of corneal reflection detection. In particular, when there are bright objects around the subject, these disturbances are reflected on the surface of the cornea, so it is difficult to distinguish them from corneal reflections. However, by making a difference, these disturbances disappear, which is very advantageous. . It should be noted that the cornea reflection image appears as an almost small point within the pupil image (the example described above) or always present in the very vicinity. On the other hand, the region of specular reflection with high luminance is large in shape. Therefore, by searching for a small point in the vicinity of the pupil, it can be distinguished from spectacle reflection.
Further, as shown in FIG. 4, the pupil is detected with a positive threshold value so that the luminance portion distribution when the dark pupil image is subtracted from the bright pupil image can be expressed in a one-dimensional manner. On the other hand, when trying to detect corneal reflection from a light source for short wavelengths (inside the aperture), the luminance of the pupil changes almost in proportion to the area of the pupil. , Thereby detecting the center (center of gravity) of the corneal reflection image by the long wavelength (outside aperture) light source, the threshold can be easily set and the robustness is improved.
Even when corneal reflection by a long wavelength (outside aperture) light source is used, it can be considered that the light source that causes the corneal reflection is present on the optical axis of the camera. It can be applied to such gaze detection.

(Second Embodiment of Pupil Detection)
In the second embodiment of pupil detection shown in FIG. 2, the configurations of the first camera, the second camera, and the short wavelength light source are not different from those of the first embodiment described above, and therefore the same numbers are used. A description thereof will be omitted. A support plate 29 having a circular hole corresponding to the opening of each camera is provided on the object side of the half mirror 10. A long-wavelength light emitting element 28a to form a long-wavelength light source 28 is disposed along the outer periphery of the circular hole.
The figure which looked at the camera side from the arrow direction which attached | subjected the front view in the figure is shown as a front view.
In this example, 14 long-wavelength light-emitting elements 28a to 28 are arranged, four long-wavelength light-emitting elements 28j to 4 are arranged, and four long-wavelength light-emitting elements 28k to 28 are arranged in a cross shape. These three examples are shown.

  When the short wavelength light source and the long wavelength light source are activated simultaneously, the short wavelength illumination light is reflected by the half mirror 10 and irradiates the face. On the other hand, long wavelength illumination light is emitted directly toward the face. When viewed from the face, the light of the short wavelength light source is emitted from within the aperture including the common optical axis of the camera, and the light of the long wavelength light source is emitted from a position circumscribing the aperture away from the common optical axis of the camera. Will be. The face image including the bright pupil image and the face image including the dark pupil image by the illumination are transmitted through the half mirror 10, transmitted through the lenses 9 and 8, separated by the half mirror 7, and have a short wavelength (850 nm). ) Passes through the band-pass filter 5 and is imaged on the short-wavelength image sensor 1 by the lens 3. The light including the long wavelength (950 nm) transmitted through the half mirror 10 and reflected and separated by the half mirror 7 is transmitted through the band pass filter 6 and is imaged on the long wavelength image sensor 2 by the lens 4.

  The outputs of the image sensors 1 and 2 are subjected to a difference calculation for each pixel by an arithmetic circuit (not shown), and a pupil image is detected. At this time, the corneal reflection region or reflection point can also be detected in the same manner as described above.

(Third embodiment of pupil detection)
In the third embodiment of pupil detection shown in FIG. 3, the configurations of the first camera and the second camera are not different from those of the first and second embodiments described above, and therefore the same numerals are assigned. The description is omitted. A substrate 32 is disposed below the half mirror 10, and seven long-wavelength light emitting elements 31a to form a long-wavelength light source 31 are disposed on the substrate as shown in the front view of the drawing. Seven short wavelength light emitting elements 30a˜ are arranged inside the long wavelength light emitting devices 31a˜.

  When the short wavelength light source and the long wavelength light source are activated at the same time, the short wavelength illumination light and the long wavelength illumination light are reflected by the half mirror 10 to irradiate the face. When viewed from the face, the light of the short wavelength light source is emitted from within the aperture including the common optical axis of the camera, and the light of the long wavelength light source is emitted from a position circumscribing the aperture away from the common optical axis of the camera. Will be. The face image including the bright pupil image and the face image including the dark pupil image by the illumination are transmitted through the half mirror 10, transmitted through the lenses 9 and 8, separated by the half mirror 7, and have a short wavelength (850 nm). ) Passes through the band-pass filter 5 and is imaged on the short-wavelength image sensor 1 by the lens 3. The light including the long wavelength (950 nm) transmitted through the half mirror 10 and reflected and separated by the half mirror 7 is transmitted through the band pass filter 6 and is imaged on the long wavelength image sensor 2 by the lens 4.

  The outputs of the image sensors 1 and 2 are subjected to a difference calculation for each pixel by an arithmetic circuit (not shown), and a pupil image is detected. At this time, the corneal reflection region or reflection point can also be detected in the same manner as described above.

  According to the pupil detection device of the present invention, the pupil can be accurately detected. By using this, it can be used in the field of human interface development in which the amount of movement of the pupil corresponds to the movement of the cursor on the personal computer screen. In addition, because pupil detection is possible even in extremely different lighting environments, it can be used in the industrial field of equipment development for driving assistance that detects the eyes of passengers and truck drivers, detects drowsiness, and detects other driving. Can also be used.

1 is an optical path diagram showing a first embodiment of a pupil detection device according to the present invention. It is an optical path diagram which shows 2nd Embodiment of the pupil detection apparatus by this invention. It is an optical path diagram which shows 3rd Embodiment of the pupil detection apparatus by this invention. It is a wave form diagram for demonstrating the principle of detection of a pupil image, and simultaneous cornea detection.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image sensor for short wavelength 2 Image sensor for long wavelength 3, 4 Lens 5 Band pass filter for short wavelength 6 Band pass filter for long wavelength 7 Half mirror (or dichroic mirror)
8 Lens 9 Objective lens 10 Half mirror 11 Parallel light 21 Short wavelength light source (for opening)
21a-21d Light emitting element for short wavelength 23a-23d Branch fiber 24 Coupling part (cylindrical lens)
25 Irradiation angle adjustment lens 26 Long wavelength light source (outside aperture)
26a Light emitting element for long wavelength 30 Light source for short wavelength (for opening)
31 Light source for long wavelengths (outside aperture)

Claims (7)

A camera means, a light source, an optical path forming means, and a computing means. By the optical path forming means, the subject is irradiated with the face from the camera means side by the light source, and an image of the face including the pupil is connected to the camera means. A pupil detection device that is arranged while maintaining an imaged relationship and calculates the imaged data to detect the pupil,
The light source is
A first illumination light source including a first wavelength component in which the reflection in the pupil of the subject becomes a bright pupil;
The subject's intra-pupil reflection includes a second wavelength component that becomes a dark pupil, and other than the pupil includes a second illumination light source that exhibits an illumination effect equivalent to that of the first illumination light source. The intensity ratio between the intensity and the second illumination light source is kept constant,
The camera means is
First image data acquisition means by the first illumination light source;
Second image data acquisition means by the second illumination light source,
The optical path forming means includes
The first image data acquisition unit and the second image data acquisition unit of the camera unit are opposed to the face with a common optical axis,
The position where the light from the first illumination light source is emitted from the opening of the common optical axis when viewed from the face side, and the light from the second illumination light source is close to the outer periphery of the opening of the common optical axis Arranged to fire from,
The pupil detection device is a means for detecting the pupil by performing arithmetic processing on the first image data and the second image data.   The first illumination light source is emitted from the opening of the common optical axis through the irradiation angle adjusting optical means by combining light emitted from a plurality of light emitting elements for short wavelengths by the optical path forming means. The pupil detection device described.   The second illumination light source emits light emitted from one or more long-wavelength light emitting elements disposed on the outer periphery of the irradiation angle adjusting optical unit from outside the opening of the common optical axis by the optical path forming unit. The pupil detection device according to claim 2.   The pupil detection device according to claim 2, wherein the light from the first and second illumination light sources is configured to be coupled via a light splitting unit disposed on the common optical axis.   3. The pupil according to claim 2, wherein the second illumination light source emits light from a plurality of light emitting elements for long wavelengths provided directly outside the opening of the common optical axis from outside the opening of the common optical axis. Detection device.   The first and second illumination light sources include a plurality of short-wavelength light-emitting elements and light emitted from one or more long-wavelength light-emitting elements arranged outside the light-emitting elements on the common optical axis. The pupil detection device according to claim 1, wherein the pupil detection device is configured to be coupled via a dividing unit. A first illumination light source including a first wavelength component that generates a bright pupil image;
A second illumination light source having a second wavelength component that generates a dark pupil image and having an intensity equivalent to that of the first illumination light source except for the pupil;
First and second imaging means for capturing an illumination image from each of the light sources, the optical systems being substantially the same and arranged on a common optical axis,
Position of the first illumination light source close to the outer periphery of the opening having a common optical axis relationship from within the openings of the first and second imaging means having a common optical axis relationship. An arrangement step of arranging so that illumination light is emitted from,
A first illumination step of activating and illuminating the first illumination light source;
A second illumination step of activating and illuminating the second illumination light source;
A data acquisition step of capturing the respective illumination images under the respective illuminations to acquire first image data and second image data;
A pupil detection method including a calculation step of detecting a pupil by performing a difference calculation process on the first image data and the second image data.

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