Eye tracking image pickup apparatus for separating noise from feature portions

An image pickup apparatus according to claim 21, wherein

• said illuminating means comprises first light sources (61) provided around an optical axis of said light separating means, each of said light sources emitting light of a first wavelength to said object;
• a first polarizing element (63) provided on light emitting surfaces of said first light sources;
• a second light source (62) provided apart from the optical axis of said light separating means for emitting light of a second wavelength to said object;
• and
• a second polarizing element (67) provided on a light emitting surface of said second light source.

An image pickup apparatus according to claim 3, wherein

• said light separating means comprises optical wavelength separating means (610) for separating reflected light of said first and second wavelengths from said object in accordance with respective wavelengths to form images;
• said polarizing plate element located on an image forming optical axis of the reflected light having the first wavelength separated by said optical wavelength separating means;
• said image generating means comprises
• first means (613) provided on the image forming optical axis of said reflected light having the first wavelength separated by said optical wavelength separating means for detecting the diffused reflected image passed by said polarizing plate, and
• second means (614) provided on an image forming optical axis of said reflected light having the second wavelength separated by said optical wavelength separating means for detecting the regularly reflected component and the diffused reflected component;
• said image pickup apparatus further comprising
• image processing means (617) responsive to detected outputs from said first and second means for forming said differential image.

An image pickup apparatus for extracting features of an image of an object, comprising:

• illuminating means (61, 62) for emitting polarized light to said object;
• first image forming means (607) for separating a part of light reflected from said object to form an image;
• second image forming means (609, 610) separating a part of the light reflected from said object and blocking a polarized regularly reflected component for providing a non-polarized diffused reflected component to form an image;
• image detecting means (612, 613) provided at image forming points of said first and second image forming means, respectively;
• and
• image processing means (618) for generating a differential image between an image formed by said first image forming means including the regularly reflected component detected by said image detecting means and an image formed by said second image forming means including only the diffused reflected component.

An image pickup apparatus for extracting features of an image of an object, comprising:

• a taking lens (65) for picking up said object;
• illuminating means (61) including a plurality of light sources (66) provided around an optical axis of said taking lens, each said light source arranged such that an angle formed by a segment coupling each said light source and the object and a segment coupling the center of said taking lens and the object is smaller than a prescribed value .theta.th;
• an optical system (607, 608, 609) for forming an image from reflected light from said object through said taking lens;
• and
• image detecting means (612, 613) provided on an image forming point of said optical system for detecting a formed image.

An image pickup apparatus for extracting features of an image of an object, comprising:

• illuminating means (113, 115) having a light emitting diode;
• driving means (110, 112, 114) for turning on/off said light emitting diode;
• an optical system (104) for forming an image from reflected light from said object;
• and
• image detecting means (105, 106) provided at an image forming point of said optical system for detecting a formed image;
• wherein
• said driving means includes means for intermittently driving said light emitting diode in synchronization with timing of detection of said image detecting means as needed.

An image pickup apparatus for extracting from an image of a face a characteristic portion necessary for eye tracking, comprising:

• illuminating means for emitting polarized light to a face which is an object to be imaged;
• light separating means for separating a reflected portion of the emitted polarized light reflected by said object to be imaged to first and second light paths and for respectively focusing each path to form respective images of the subject;
• a polarizing plate provided on one of the light paths separated by said light separating means for blocking a regular reflection component of said reflected portion of the polarized light and for passing a diffused reflection component thereof;
• and
• image generating means for generating a differential image of the respective images focused by said light separating means.

An image pickup apparatus for extracting from an image of a face a characteristic portion necessary for eye tracking, comprising:

• a first light source provided near an optical axis of a photographing lens, a first angle defined between a line segment connecting the first light source and an eyeball which is an object to be photographed and a line segment connecting the center of said photographing lens and the object, said first angle being smaller than a prescribed value .theta.th.sub.1 ;
• a second light source spaced apart from the optical axis of said lens by a prescribed distance, a second angle defined between a line segment connecting the second light source and the object and a line segment connecting the center of said photographing lens and said object, said second angle being larger than a prescribed value .theta.th.sub.2 ;
• an optical system for separating light from said first light source reflected by said object and light from said second light source reflected by said object and for respectively focusing said light from said first and second light sources reflected by said object to form respective images thereof;
• and
• image generating means for generating a differential image of said respective images focused by said optical system.

An image pickup apparatus as recited in claim 23, wherein said first light source includes polarizing means thereby to emit polarized light to the eyeball to be photographed;

• and further comprising
• light separating means for separating a reflected portion of the polarized light reflected by said object to be imaged to first and second light paths and for respectively focusing each path to form respective images of the eyeball;
• a polarizing plate provided on one of the light paths separated by said light separating means for blocking a regular reflection component of said reflected portion of the polarized light and for passing a diffused reflection component thereof;
• and
• second image generating means for generating a second differential image of the respective images focused by said light separating means,
• whereby said second differential image generated by said second image generating means substantially eliminates images of background features, thereby emphasizing an image of a cornea of the eyeball and distinguishing the cornea from images of background features.