JP2009112431A5 - - Google Patents

Claims (3)

In an eye dimension measuring apparatus having a measuring unit that measures a dimension of an anterior ocular segment by irradiating the anterior ocular segment of a subject eye with low coherent light and receiving reflected light from the anterior ocular segment as an interference light ,
Driving means for three-dimensionally moving the measurement unit with respect to the eye to be examined;
An alignment projection optical system that projects alignment light toward the eye to be examined; and
Alignment detection means for receiving reflected light from the anterior eye portion due to the alignment light by an image sensor and detecting misalignment of the measurement portion with respect to the eye to be examined
A fixation guidance means for guiding the fixation direction of the eye to be examined by moving the presentation position of the fixation target to be presented to the eye to be matched with the measurement optical axis of the measurement optical system;
Based on the detection result of the alignment detection means, the eye to be examined and the measurement unit are aligned using the driving means so as to have a predetermined positional relationship, and then the measurement optical axis and the measurement target are measured using the fixation guidance means. Presenting the fixation target for matching the optometry optical axis, and using the driving means to re-establish the predetermined positional relationship with respect to the misalignment caused by the fixation target presentation. Control means for driving control;
An eye dimension measuring device comprising: The eye dimension measuring device according to claim 1 comprises:
Further, a predetermined luminous flux is irradiated toward the eye to be examined, the corneal vertex luminescent spot and the front luminescent spot of the lens obtained by irradiation of the luminous flux are received, and an anterior ocular segment luminescent spot acquisition means is provided, and the control means includes the The fixation target is controlled to be presented by the fixation guiding means so that the corneal vertex luminescent spot obtained by the anterior eye luminescent spot acquisition means and the front luminescent spot of the crystalline lens are superimposed on the light receiving surface. Eye dimension measuring device. In the eye dimension measuring device according to claim 2,
The fixation guidance means includes
A fixation light source emitted toward the eye to be examined;
An imaging optical system that forms an image of a fixation light beam emitted from a fixation light source on the fundus of the eye to be examined;
An optical deflection unit that is provided in the optical path of the imaging optical system and deflects the fixation light beam emitted from the fixation light source two-dimensionally so that the fixation direction of the eye to be examined is guided;
Drive control means for driving and controlling the light deflection unit to match the measurement optical axis of the measurement optical system with the optical axis of the eye to be examined;
An eye dimension measuring apparatus comprising: