Visual axis detection device capable of reducing detection errors due to variations of eyes among individuals

A visual axis detection apparatus, comprising:

• calculating means for detecting rotation angle information of an eyeball of an observer, calculating an individual variation of the visual axis of the observer, and determining a direction of the visual axis from the rotation angle information;
• targeting means for causing the observer to watch visual targets attentively, and collecting rotation angle information several times;
• and
• correction means for calculating a mean value of a plurality of rotation angle information values, and a difference between each of the plurality of rotation angle information values and the mean value, extracting correct rotational angle information by comparing each of the calculated differences with a threshold value, and forming correction information for correcting a personal difference of the visual axis based on the extracted correct rotational angle information.

A visual axis detection apparatus, comprising:

• photodetecting means to receive light from an eyeball of an observer;
• calculation means to calculate the rotation angles of the eyeball from the eyeball images of the observer obtained by said photodetecting means, correct the individual variations of the visual axis of the observer from the said rotation angles, and obtain the observing positions on the observation plane;
• and
• means to calculate said visual axis correction data by excluding the rotation angles having difference between the mean value .theta. of the rotation angles of the eyeball and each of the rotation angles of the eyeball which is greater than a given value .theta.th in order to obtain the visual axis correction coefficients to correct the individual variations of the visual axis by detecting the rotation angles of the eyeball of the observer plural times.

A method for determining a rotational angle of an eyeball, comprising the steps of:

• detecting a plurality of data values corresponding to the rotational angle;
• identifying improper data values from among the plurality of data values;
• and
• obtaining the rotational angle of the eyeball using data values corresponding to the rotational angle excluding the improper data values.

A visual axis detection apparatus comprising:

• a sensor that supplies an electrical signal that varies in accordance with rotation of an eyeball;
• and
• a signal processing apparatus that receives the electrical signal and detects direction of a visual axis of the eyeball,
• wherein said signal processing apparatus forms a plurality of data values corresponding to a rotational angle of the eyeball, identifies improper data values from among the plurality of data values, and obtains the rotational angle of the eyeball using data corresponding to the rotational angle excluding improper data values identified by said signal processing apparatus.

A visual axis detection method comprising the steps of:

• storing information relating to a personal eyeball;
• detecting a rotational angle of the eyeball;
• detecting a direction of a visual axis of the eyeball using personal data formed by information stored in the storing step and the rotational angle detected in the detecting step;
• and
• renewinq a value of personal data using information previously stored in the storing step and new information input when new information relating to the eyeball is detected.

A visual axis detection apparatus comprising:

• a sensor that supplies an electrical signal that varies in accordance with rotation of an eyeball;
• storing means for storing information relating to an eyeball of a person;
• and
• a signal processing apparatus that receives the electrical signal and detects a direction of a visual axis of the eyeball, wherein said signal processing apparatus detects a rotational angle of the eyeball based on the electrical signal and detects the direction of the visual axis of the eyeball using personal data formed by information stored in said storing means and the rotational angle, and
• wherein the signal processing apparatus renews the personal data formed by the information stored in said storing means using stored information and new information when new information relating to the eyeball is detected.

An optical apparatus comprising:

• a sensor that supplies an electrical signal that varies in accordance with rotation of an eyeball;
• storing means for storing information relating to a personal eyeball;
• and
• a signal processing apparatus that receives the electrical signal and detects a direction of a visual axis of the eyeball, wherein said signal processing apparatus detects a rotational angle of the eyeball based on the electrical signal and detects the direction of the visual axis of the eyeball using personal data formed by stored information and the rotational angle, and renews a value of the personal data using stored information and new information when new information relating to the eyeball is detected.