Apparatus for measuring an intraocular length between anterior and posterior portions of an eye

An apparatus for measuring an intraocular length between anterior and posterior portions of living eye, comprising:

• a laser source to emit a laser beam of light, having variable wavelengths, onto said eye;
• and
• means for measuring interference between light reflected by said anterior portion of said eye and light reflected by said posterior portion of said eye,
• the intraocular length being measured according to said interference,
• said measuring interference means comprising:
• a light receiving optical system for receiving interference light;
• an anterior portion illuminating optical system for projecting said laser beam of light onto the anterior portion and guiding light reflected by the anterior portion to said light receiving optical system;
• and
• a posterior portion illuminating optical system for projecting said laser beam of light onto the posterior portion and guiding light reflected by the posterior portion to said light receiving optical system;
• said anterior portion illuminating optical system and said posterior portion illuminating optical system being arranged so that the reflected light from the anterior and posterior portions interferes with each other at a substantially identical wave front and is guided to said light receiving optical system.