JPH10165371A - Sight line measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly accurately detect the direction of a sight line, for example, when the eyes of an automobile driver in travel look in the front direction, reduce the whole size of the device, and produce it at a low cost by improving the arrangement constitution of respective parts of a lens system, a light source, a semi-reflecting mirror, and a light receiving part for constituting a sight line measuring device. SOLUTION: The device is so constituted that a light source 4 for irradiating a light of a specific wavelength to a measuring object is arranged coaxial with a lens system 1, and a semi-reflecting mirror 3 which transmits the light approximately half of the light of the specific wavelength emitted by the light source 4 and reflects the residual half light is inclinedly arranged between the light source 4 and the lens system 1. It is so constituted that a light receiving part 2 for picking up an image of the measurement object is arranged on the optical axis of the light reflected by the semi-reflecting mirror 3 out of the light incident from the lens system 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used to detect the direction of a line of sight from the positional relationship between a corneal reflection image and a pupil image obtained when light of a specific wavelength is irradiated on a human eye to be measured. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line-of-sight measuring device, for example, a line-of-sight measuring device suitable for detecting a line-of-sight direction when an eye of a driver of a running automobile looks ahead.

[0002]

2. Description of the Related Art FIG. 7 shows a currently proposed line-of-sight measuring device. FIG. 7 is an explanatory view showing the operating principle of the proposed eye gaze measuring apparatus, and FIG.
FIG. 8 is a cross-sectional view schematically illustrating a configuration of the eye gaze measuring device in FIG. 7. 7 and 8, reference numeral 1 denotes a lens system for obtaining a predetermined angle of view, 2 denotes a light receiving unit arranged on the same axis as the lens system 1, and 3 denotes a position between the lens system 1 and the light receiving unit 2. The mirror is a semi-reflective mirror disposed at an angle, and usually uses a half mirror that transmits only light of a specific wavelength.

A light source 4 emits light of a specific wavelength. The light source 4 is disposed on an optical axis of light incident from the lens system 1 and reflected by the semi-reflecting mirror 3.
Reference numeral 5 denotes a lens barrel, in which the lens system 1, the light receiving unit 2, the semi-reflective mirror 3, and the light source 4 are held. 7 is an integrated circuit (IC: integrated ci)
Rcuit) and a circuit board on which a circuit component such as an Rcuit) is mounted. On this circuit board 7, a lens cylinder 5 is mounted.

In the eye gaze measuring apparatus having the structure shown in FIGS. 7 and 8, light of a specific wavelength emitted from the light source 4 is halved by the semi-reflecting mirror 3, and the reflected light is emitted from the lens system 1 to the outside. Is done. When the light emitted from the lens system 1 is applied to a human eye (not shown) to be measured,
The light reflected by the eye (pupil) is incident on the lens system 1 again together with unnecessary light (noise light) such as external light. The incident reflected light passes through the semi-reflective mirror 3 and is halved, and directly enters the light receiving section 2 together with unnecessary light. Based on the reflected light of the light source 4 incident on the light receiving unit 2, image processing of a human eye as a measurement target is performed.

[0005]

As described above, FIG.
8, the light-receiving unit 2 is provided on the same axis as the lens system 1, and the light source 4 is provided on the longitudinal side surface of the lens barrel 5. It has the structure which was done. Therefore, when the lens barrel 5 is mounted on the circuit board 7, as shown in FIG. 8, the lens cylinder 5 is inevitably mounted on the circuit board 7 with the longitudinal side surface facing in the vertical direction (upright direction). Because of the configuration, a useless mounting space (space portion) 6 having a height substantially equivalent to the length of the lens barrel 5 is formed on the upper surface of the circuit board 7 as indicated by a portion surrounded by a broken line in FIG. Therefore, there is a problem that it is impossible to make the whole size small.

Therefore, in order to reduce the size of the entire configuration of the eye-gaze measuring device, if the lens cylinder 5 is mounted on the circuit board 7 in the horizontal direction (horizontal direction), the circuit board 7 may be damaged. The problem is that it is necessary to use a flexible circuit board that can bend the part in a right angle direction, and extra circuit parts such as connectors are required, which complicates the configuration and raises the cost. was there.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and irradiates light of a specific wavelength onto a measurement object on the same axis as a lens system for obtaining a predetermined angle of view. And a half-reflecting mirror between the light source and the lens system that transmits approximately half of the light of a specific wavelength emitted by the light source and reflects the other half of the light. The light receiving unit for capturing the image of the measurement object is arranged on the optical axis of the light reflected by the semi-reflecting mirror among the light incident from the lens system, so that When mounted on the circuit board based on the arrangement of each component,
An object of the present invention is to provide an eye-gaze measuring device that can easily achieve miniaturization of the entire size and can be configured at a low cost because unnecessary mounting space is eliminated.

[0008]

According to a first aspect of the present invention, there is provided an eye-gaze measuring apparatus which irradiates a measurement object with light having a specific wavelength on the same axis as a lens system for obtaining a predetermined angle of view. And a half-reflecting mirror between the light source and the lens system for transmitting approximately half of the light of a specific wavelength emitted by the light source and reflecting the other half of the light. It is characterized in that a light receiving unit for capturing an image of a measurement target is arranged on an optical axis of light reflected by a semi-reflecting mirror among light incident from a lens system. I do.

According to a second aspect of the present invention, there is provided an eye-gaze measuring apparatus according to the first aspect, wherein the light source is an infrared light emitting diode (infrared LED) which is an infrared light source that emits infrared light. Is used.

According to a third aspect of the present invention, in the sight line measuring device according to the first or second aspect, the semi-reflective mirror includes an infrared ray substantially half an infrared light emitted from the infrared LED. A semi-reflective mirror for infrared light (half mirror for infrared light) that transmits light and reflects the remaining half of infrared light is used.

According to a fourth aspect of the present invention, there is provided the eye-gaze measuring device according to the first aspect, wherein the light receiving unit is a charge-coupled device (CCD) as a light-receiving element. .

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An eye gaze measuring apparatus according to the present invention has a lens system, a light source, a semi-reflecting mirror, and a light receiving section, which constitute the eye gaze measuring apparatus, arranged on the same axis as the lens system. A light source is provided, and a semi-reflecting mirror is disposed between the light source and the lens system at an angle, and a light receiving unit is provided on the optical axis of light reflected by the semi-reflecting mirror among light incident from the lens system. Since it is configured to be disposed, it is used, for example, in the case where the driver's eyes of a running automobile detect the line of sight when the driver looks at the front direction with high accuracy, and is extremely optimal to implement. Things.

[0013]

Embodiments of the present invention will be described below.
FIG. 1 is an explanatory view showing an operation principle of a visual line measuring device according to an embodiment of the present invention, FIG. 2 is a sectional view schematically showing a configuration of the visual line measuring device in FIG. 1, and FIG. 3 is mounted on a circuit board. Fig. 2
FIG. 4 is a partial cross-sectional view schematically showing a configuration in which the eye-gaze measuring device is housed in a case, FIG. 4 is an explanatory view showing a state in which the eye-gaze measuring device of FIG. 2 is mounted in a car, and FIG. FIG. 6 is an explanatory diagram showing a mode of detecting the gaze direction of the eyes of the driver of the vehicle as the measurement target by the gaze measurement device of FIG. 6, and FIG. 6 is a diagram of the driver of the measurement target vehicle obtained by the gaze measurement device of FIG. It is a figure showing an image of an eye.

1 to 3, reference numeral 1 denotes a lens system for obtaining a predetermined angle of view, and reference numeral 4 denotes a light source which emits light of a specific wavelength disposed on the same axis as the lens system 1. Light source 4
As an infrared light emitting diode (LED: light emitting diode) which is an infrared light source that emits infrared light.
e) is used. Numeral 3 denotes a semi-reflecting mirror which is disposed between the lens system 1 and the light source 4 so as to be inclined. The semi-reflecting mirror 3 has an infrared ray substantially half of the infrared light emitted from the light source 4 (infrared LED). A semi-reflecting mirror for infrared light (half mirror for infrared light) that transmits light and reflects the remaining half of infrared light is used.

Reference numeral 2 denotes light (infrared light) incident from the lens system 1.
The light receiving unit is disposed on the optical axis of the light reflected by the semi-reflective mirror 3 (semi-reflective mirror for infrared light), and captures an image of a measurement target (not shown). 2 as a charge-coupled device (CCD: charge
e coupled device). Reference numeral 5 denotes a lens barrel, in which the lens system 1, the light receiving unit 2, the semi-reflective mirror 3, and the light source 4 are held. Reference numeral 7 denotes a circuit board on which circuit components such as an integrated circuit (IC) are mounted. The circuit board 7 is mounted on the circuit board 7 with the longitudinal side surface of the lens barrel 5 oriented in the horizontal direction (horizontal direction). I have. Reference numeral 8 denotes a case housing the line-of-sight measuring device mounted on the circuit board 7, 9 denotes a support of the case 8, and 10 denotes a lens system 1.
Or an opening provided in the case 8 for light to be emitted or light to be incident on the lens system 1.

A shown in FIG. 4 is a gaze measuring apparatus according to the present invention mounted on a part of an instrument panel in front of a driver's seat in an automobile, for example, and B shown in FIG.
Viewing angle of the eye-gaze measuring device A, C shown in FIG.
Is a line of sight in the direction in which the driver's eye of the automobile to be measured looks. A display or the like (not shown) of a navigation system is arranged ahead of the line of sight (arrow C). D shown in FIG. 6 is an image of the eye of the driver of the automobile, which is the measurement target, obtained by the eye gaze measuring apparatus A of FIG.

The gaze measuring apparatus according to the present invention is configured as shown in FIGS. 1 to 3, and a light of a specific wavelength emitted from a light source 4 (infrared LED), that is, an infrared light is a semi-reflective mirror. 3 (a half-reflecting mirror for infrared light), and the half-reduced infrared light is emitted from the opening 10 of the case 8 through the lens system 1 and at a distance of about 50 cm or more in front of the lens system 1. The light is radiated to a human eye (not shown) that is located and is a measurement target. In this case, the emitted light of the infrared light emitted from the light source 4 may be reflected by the lens surface of the lens system 1 through the semi-reflective mirror 3 and directly enter the light receiving unit 2. In addition, a coating is provided to prevent reflection of infrared light having a wavelength of outgoing light. The reflected infrared light reflected by the human eye (pupil) is combined with unnecessary light (noise light) such as external light in case 8.
The light is again incident on the lens system 1 through the opening 10.

Of the light incident on the lens system 1, only unnecessary light passes through the semi-reflective mirror 3 and escapes in the direction where the light source 4 is located. The reflected infrared light, which is necessary light, is halved by the semi-reflective mirror 3, reflected, and enters the light receiving section 2 (CCD, which is a light receiving element). Based on the reflected infrared light incident on the light receiving unit 2, image processing of the human eye as the measurement target is performed, whereby measurement of the line of sight of the human eye can be performed.

In the eye gaze measuring apparatus of the present invention shown in FIG. 2, the light receiving section 2 is not disposed on the same axis as the lens system 1, and the light receiving section 2 is provided on the side surface of the lens cylinder 5 in the longitudinal direction.
Is provided, and has a configuration in which the longitudinal side surface of the lens barrel 5 is mounted on the circuit board 7 in the lateral direction (horizontal direction). Therefore, the length of the back focus of the lens system 1 of the eye-gaze measuring device can be effectively used as a mounting surface for the light receiving unit 2 on the circuit board 7, and the configuration shown in FIG. In comparison, since there is no useless mounting space, there is an advantage that the overall size can be easily reduced in size and the configuration can be made at low cost.

As shown in FIG. 4, when the gaze measuring apparatus A according to the present invention is mounted on a part of an instrument panel in front of a driver's seat in an automobile, for example, the measurement is performed as shown in FIG. The viewing angle B of the line-of-sight measuring device A with respect to the driver's eye of the target vehicle is indicated by a hatched area, and the line of sight C in the direction that the driver's eye of the vehicle looks is indicated by a dashed arrow. Indicated by Further, an image D of the eye of the driver of the automobile, which is the measurement target, obtained by the eye gaze measuring device A is as shown in FIG.

[0021]

As described above, according to the eye-gaze measuring apparatus of the first aspect of the present invention, light of a specific wavelength is applied to the object to be measured on the same axis as the lens system for obtaining a predetermined angle of view. A light source for irradiating is provided, and a semi-reflecting mirror for transmitting approximately half of the light of a specific wavelength emitted by the light source and reflecting the other half of the light is provided between the light source and the lens system. Arranged at an angle,
A light receiving unit for capturing the image of the measurement target is arranged on the optical axis of the light reflected by the semi-reflecting mirror among the light incident from the lens system. When mounted on a circuit board, there is no useless mounting space, so that the overall size can be easily reduced in size, and excellent effects such as being able to be configured at low cost are achieved. .

According to a second aspect of the present invention, in the visual axis measuring device according to the first aspect, the light source is an infrared light emitting diode (infrared LED) which is an infrared light source that emits infrared light.
Infrared light, which is invisible to the human eye, is used as the light emitted from the light source, so that the gaze measurement processing of the measurement target can be performed sufficiently even in a relatively dark environment. There is an effect that can be.

According to a third aspect of the present invention, in the eye gaze measuring device according to the first or second aspect, the semi-reflective mirror includes:
A configuration using a half-mirror for infrared light (half mirror for infrared light) that transmits approximately half of the infrared light emitted from the infrared LED and reflects the other half of the infrared light. Therefore, a half-reflecting mirror that transmits substantially half of the infrared light that cannot be seen by the human eye and reflects the other half is used. There is an effect that the gaze measurement processing of the measurement target can be sufficiently performed even in a dark environment.

According to a fourth aspect of the present invention, in the eye-gaze measuring device according to the first aspect, the light receiving section is configured to use a charge-coupled device (CCD) as a light receiving element. The use of a small and light-weight, low-power, long-life, and vibration-resistant element makes it possible to reduce the overall size, and also has the effects of reducing cost and labor.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an operation principle of a visual line measuring device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically showing a configuration of the eye gaze measuring device of FIG.

FIG. 3 is a partial cross-sectional view schematically showing a configuration in which the visual line measuring device of FIG. 2 mounted on a circuit element is housed in a case.

FIG. 4 is an explanatory diagram showing an aspect in which the eye gaze measuring device of FIG. 2 is mounted inside a vehicle.

FIG. 5 is an explanatory diagram showing an aspect in which the line-of-sight direction of the driver's eye of the automobile to be measured is detected by the line-of-sight measuring device of FIG. 2;

FIG. 6 is a diagram showing an image of an eye of a driver of an automobile, which is a measurement target, obtained by the eye gaze measuring device of FIG. 2;

FIG. 7 is an explanatory diagram showing the operation principle of the proposed eye gaze measuring device.

8 is a cross-sectional view schematically showing the configuration of the eye gaze measuring device of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lens system 2 Light receiving part (CCD) 3 Semi-reflection mirror (half mirror for infrared light) 4 Light source (infrared LED) 5 Lens cylinder 6 Useless mounting space (space part) 7 Circuit board 8 Case 9 Support stand 10 Aperture

Claims (4)

[Claims] An eye gaze measuring device for detecting a gaze direction from a positional relationship between a corneal reflection image and a pupil image obtained when light of a specific wavelength is irradiated to an eye to be measured, and obtains a predetermined angle of view. And a light source arranged on the same axis as the lens system for irradiating light of a specific wavelength to the object to be measured, and an inclined arrangement between the light source and the lens system And a semi-reflecting mirror for transmitting substantially half of the light of the specific wavelength emitted by the light source and reflecting the remaining half of the light, and of the light incident from the lens system, reflected by the semi-reflecting mirror. An eye-gaze measuring device, comprising: a light-receiving unit disposed on an optical axis of the emitted light and configured to capture the image of the measurement target. 2. The eye gaze measuring device according to claim 1, wherein an infrared light emitting diode (infrared LED) that is an infrared light source that emits infrared light is used as the light source. . 3. The eye-gaze measuring device according to claim 1, wherein the semi-reflecting mirror transmits substantially half of the infrared light emitted from the infrared LED and the other half of the infrared light. A line-of-sight measuring device using a semi-reflecting mirror for infrared light that reflects light (half mirror for infrared light). 4. The eye gaze measuring device according to claim 1, wherein the light receiving section is a charge coupled device (CC) which is a light receiving element.
An eye gaze measuring apparatus using D).