| 主权项 |
1. An anterior eye segment measuring apparatus comprising:
a light projecting optical system for projecting light emitted from a light source on an anterior eye segment of an examinee's eye and forming a light section of the light before the light enters into the anterior eye segment and after the light enters into the anterior eye segment; a light receiving optical system, including a detector for receiving anterior eye segment scattered light acquired by scattering of the light section at the anterior eye segment, for obtaining a cross-sectional image; a detecting optical system for detecting displacement of an actual cross-sectional image from an acquisition position of an expected cross-sectional image; a displacement detection unit for detecting displacement in a Y-axis direction between an actual position where the light section enters into the examinee's eye and an expected position where the light section is expected to enter into the examinee's eye based on a detection result obtained by the detecting optical system, the Y-axis direction being orthogonal to the light section of the light before the light enters into the anterior eye section and orthogonal to a lateral direction of the examinee's eye; and a controller for forming the cross-sectional image of the anterior eye segment based on a detection signal from the displacement detection unit and processing the cross-sectional image to measure the anterior eye segment, wherein the controller corrects a measurement result of the anterior eye segment based on the displacement in the Y-axis direction detected by the displacement detection unit, the measurement result comprising a curvature radius, and the measurement result further comprising an anterior chamber depth or a corneal thickness, when the light emitted from the light source is slit light, the displacement in the Y-axis direction is in a direction orthogonal to a longitudinal direction of the slit light, when the light emitted from the light source is scanning light, the displacement in the Y-axis direction is in a direction orthogonal to a scanning direction of the light emitted from the light source, the curvature radius is corrected by using the following equation:
R1=√{square root over (R22+ΔY2)} where R1 represents a corrected curvature radius, R2 represents the curvature radius in the measurement result and ΔY represents the displacement in the Y-axis direction, when the measurement result comprises the corneal thickness, the corneal thickness is corrected by using the following equation:
D1=D1′+d1−d 2 where D1 represents a corrected corneal thickness, D1′ represents the corneal thickness in the measurement result, d1 represents an amount of displacement between a corrected corneal curvature radius at an anterior surface and a corneal curvature radius at the anterior surface in the measurement result, and d2 represents an amount of displacement between a corrected corneal curvature radius at a posterior surface and a corneal curvature radius at the posterior surface in the measurement result, and when the measurement result comprises the anterior chamber depth, the anterior chamber depth is corrected by using the following equation:
D2 =D2′+d2−d3 where D2 represents a corrected anterior chamber depth, D2′ represents the anterior chamber depth in the measurement result, and d3 represents an amount of displacement between a corrected curvature radius at an anterior surface of a crystalline lens and a curvature radius at the anterior surface of the crystalline lens in the measurement result. |
