Canon Kabushiki Kaisha

Toshifumi Masaki

Kyoji Sekiguchi

Motoya Takai

Yukio Sakagawa

Shinya Tanaka

Shigeaki Ono

Hiroshi Aoki

Tomoyuki Iwanaga

Takashi Masuda

Masao Shikaumi

Satoshi Aikawa

Toshiaki Okumura

Koji Uchida

Wataru Sakagawa

Yuki Shimozato

Yoshimasa Hamano

Hideyuki Ooban

Satoshi Shimashita

The present invention reduces a positional displacement of an acquired image attributable to a delay from the issuance of a drive instruction to a scanner to the scanner actually reaching an instructed drive position. An ophthalmologic apparatus has a light scanning unit which scans measuring light on an eye to be examined, an acquisition unit which receives light reflected from the eye to be examined and acquires a light receiving signal, and an instruction unit which instructs the drive position of the light scanning unit. The apparatus further includes a position detection unit which detects the current position of the light scanning unit and a measurement unit which measures the drive time delay from the issuance of an instruction by the instruction until the current position reaches the instructed drive position. The acquisition unit starts acquiring the light receiving signal at timing based on the drive time delay.

Ophthalmologic apparatus and control method thereof

An optical tomographic imaging apparatus includes a measurement light optical path length changing unit configured to change an optical path length of measurement light. In a case where any one of a plurality of imaging regions of an object (for example, a region of an anterior eye of a subject's eye and a region of a fundus of the subject's eye) is selected, the optical tomographic imaging apparatus can control the measurement light optical path length changing unit according to a size of an imaging range of a tomographic image corresponding to the selected imaging region.

Optical tomographic imaging apparatus and method for controlling the same

An ophthalmologic apparatus includes an integration unit configured to integrate a light emission amount of a light source for illuminating a subject's eye, a comparison unit configured to compare an integration value by the integration unit with a first reference value, and an initialization unit configured to initialize the integration value if the integration value exceeds the first reference value as the comparison result by the comparison unit.

Ophthalmologic apparatus

An ophthalmologic apparatus includes an integration unit which integrates a light emission amount of a light source illuminating an target eye, an integral capacitance changing unit which changes a value of an integral capacitance of the integration unit according to the light emission amount necessary for imaging the target eye, a comparison unit which compares a reference value with an integration value integrated by the integration unit using the value of the integral capacitance changed by the integral capacitance changing unit, and a light emission control unit which stops the light emission of the light source when the integration value exceeds the reference value as a result of the comparison by the comparison unit.

In an ophthalmologic apparatus in which a head part is moved at a speed according to a rotation speed of a rotational part of a joystick, in order to enable a moving amount of the head part to correspond to a rotation amount even when the rotation speed becomes higher, the rotation speed of the joystick is detected at predetermined intervals, and when a current rotation speed (count of an encoder during a predetermined period) is lower than a previous rotation speed, a speed obtained by subtracting a predetermined value from the previous rotation speed is compared to the current rotation speed. Then, a higher speed is set as the current rotation speed, and the head part is moved at the speed corresponding to the current rotation speed.

Control apparatus, control method, and ophthalmologic apparatus including the control apparatus

When an observation state by an infrared LEDis changed to a photographing state by a xenon lamp, a movable mirroris pulled upward and an optical path is switched to an image sensorside. A light guideis shifted by an alignment index drive motorso that an incident portion of an alignment index is shifted from a visible LEDto direct to an infrared LED. An outgoing portion of the light guideis set at a position where an image is formed on the image sensorby a wavelength of the infrared LEDwhen an operation distance is appropriate. While changing a luminescent color, a position of a luminescent point of the alignment index is changed by switching the LED by the shift of the light guide

Ophthalmologic photographing apparatus

A fundus camera that obtains focus evaluation values by scanning, in which a focusing lens moves a predetermined distance according to a photographing mode before the focusing lens starts scanning for obtaining focus evaluation values.

Fundus camera

A fundus camera includes an observation photographing unit having a focusing lens to perform focusing of an imaging unit on a fundus of a subject's eye, a lens driving unit configured to drive the focusing lens in an optical axis direction, and a focusing control unit configured to calculate a focusing evaluation value based on image information of a predetermined area of a fundus image captured by the observation photographing unit, and drive the focusing lens based on the focusing evaluation value, thereby performing focusing, wherein the focusing control unit moves the focusing lens from a previous photographing position of the focusing lens by a predetermined moving amount, and then performs the focusing.

A single-plate image pickup element picks up an eye fundus image. A tricolor separation color filter includes R, G, and B filter elements arranged in a mosaic so as to correspond to the pixels of the image pickup element. Each virtual pixel value of color image data is calculated from light detection data of adjacent pixels. Thus, image data of a color still image is generated. The R filter elements transmit near-infrared light. Each virtual pixel value is calculated from light detection data of pixels corresponding to B or G filter elements that are adjacent to the R filters and have sensitivity to near-infrared light. Thus, image data of a near-infrared light monochrome moving image is generated.

Eye fundus camera

A non-contact tonometer changes a reference signal used for determining reliability of a signal indicating deformation of a cornea based on the reflectance of the cornea of an eye to be examined. Thus, the non-contact tonometer can perform stable measurement irrespective of the reflectance of the cornea of the eye to be examined.

Non-contact tonometer

In an ophthalmologic apparatus, the coordinates of three illuminated spots on a cornea-reflected image calculated from a front eye part image picked up by a two-dimension image pickup element and a pupil diameter are calculated, and the position of the centroid of the pupil is calculated from the front eye part image. When the pupil diameter is smaller than a predetermined value, alignment is effected from the shift from the center of the pupil, and when the pupil diameter is larger than the predetermined value, alignment is effected on the basis of the shift amounts from the illuminated spots on the cornea-reflected image. Also, a controlling method is changed over by the difference between the positions of the illuminated spots on the cornea-reflected image and the position of the centroid of the pupil. Also, the tolerance level of alignment is varied by the size of the pupil diameter.

Opthalmologic apparatus

In order to accurately align an eye examining portion with the center of the pupil, (a) the interval d between illumination light source images PL and PR is an interval obtained when the operation distance has been properly position-aligned by other alignment means. (b) shows an interval din a state in which the operation distance is longer than to a proper position, and (c) shows an interval din a state in which the operation distance is shorter than the proper position. Even if the operation distance fluctuates when position alignment is effected with the center of the pupil, whereby the interval becomes dand das shown in (b) and (c), a measuring portion is moved in front to rear direction and is made coincident with the reference interval d, as shown in (a), whereby a proper operation distance is obtained.

Ophthalomologic apparatus

An aligning method for an ophthalmologic apparatus including a measurement optical system for measuring the eyes of an object to be examined and an illumination system for illuminating the eyes with extrinsic eye light is disclosed. When a reflected cornea image can be detected by irradiating an eye of the object with alignment light, alignment of the measurement optical system is executed on the basis of the reflected cornea image. If no reflected cornea image of the alignment light can be detected, a reflected cornea image formed by the extrinsic eye light is detected, and alignment of the measurement optical system is executed on the basis of the reflected cornea image formed by the extrinsic eye light. Thereafter, the reflected cornea image is detected again.

Growing community of inventors

Tokyo, Japan

Toshifumi Masaki