Beam steering optical system and method and ophthalmic apparatus using same having spaced apart irradiation and observation paths

An ophthalmic apparatus comprising:

• an irradiating optical system comprising at least one light source producing at least one irradiating light beam for irradiating an eye;
• an objective lens positioned to receive the at least one irradiating light beam to focus the at least one irradiating light beam on the eye;
• a detecting optical system, comprising at least one photodetector, for receiving at least one detecting light beam comprising the at least one irradiating light beam reflected by the eye;
• and
• a beam steering optical system, having a system pupil, comprising:
• a two-sided rotatable mirror positioned to cover only a first portion of the system pupil and to reflect with a first surface thereof the at least one irradiating light beam received from said irradiating optical system and to reflect to said at least one photodetector with a second surface thereof the at least one detecting light beam reflected by the eye;
• and
• beam redirecting means for redirecting one of the at least one irradiating light beam and the at least one detecting light beam;
• wherein said irradiating optical system and said at least one photodetector are positioned so that one of the following occurs:
• the at least one irradiating light beam is reflected by the first surface of said two-sided rotatable mirror to said beam redirecting means which redirects the at least one irradiating light beam through a second portion of the system pupil not covered by said two-sided rotatable mirror and then through said objective lens to the eye;
• and
• the at least one detecting light beam reflected by the eye passes through the second portion of the system pupil not covered by said two-sided rotatable mirror to said beam redirecting means, and is redirected by said beam redirecting means to the second surface of said two-sided rotatable mirror which reflects the at least one detecting light beam to said at least one photodetector,
• wherein said objective lens makes the pupil of the eye conjugate with the system pupil,
• wherein said irradiating optical system, said two-sided rotatable mirror, and said objective lens together define an irradiation path for the at least one irradiating light beam;
• wherein said objective lens, said two-sided rotatable mirror, and said detecting optical system together define an observation path for the at least one detecting light beam,
• wherein said two-sided rotatable mirror steers both the at least one irradiating light beam and the at least one detecting light beam through the same angle when said two-sided rotatable mirror rotates, and
• wherein the irradiation path and the observation path are spaced from each other at least at the system pupil.

A beam steering method for steering a beam in a beam steering system having a system pupil, comprising:

• a first step of producing at least one irradiating light beam with an irradiating optical system for irradiating an object and projecting the at least one irradiating light beam to a first portion of the system pupil;
• a second step of reflecting the at least one irradiating light beam at the first portion of the system pupil with a first surface of a two-sided rotatable mirror to the object;
• wherein said first and second steps together define an irradiation path for the at least one irradiating light beam;
• a third step of reflecting the at least one irradiating light beam from the object as at least one detecting light beam to a second surface of the two-sided rotatable mirror, and reflecting the at least one detecting light beam from the second surface of the two-sided rotatable mirror to a photodetector;
• a fourth step of redirecting one of the at least one irradiating light beam and the at least one detecting light beam;
• a fifth step of positioning the irradiating optical system and the photodetector so that one of the following sequences of steps occurs:
• reflecting the at least one irradiating light beam with the first surface of the two-sided rotatable mirror, and redirecting the reflected at least one irradiating light beam, reflected by the first surface of the two-sided rotatable mirror, through a second portion of the system pupil not covered by the two-sided rotatable mirror to the object;
• and
• projecting the at least one detecting light beam reflected by the object through the second portion of the system pupil not covered by the two-sided rotatable mirror, redirecting the at least one detecting light beam having passed through the second portion of the system pupil to the second surface of the two-sided rotatable mirror, and reflecting the at least one detecting light beam from the second surface of the two-sided rotatable mirror to the photodetector;
• and
• a sixth step of steering both the at least one irradiating light beam and the at least one detecting light beam through the same angle when the at least one irradiating light beam is reflected by the first surface of the two-sided rotatable mirror and when the at least one detecting light beam is reflected by the second surface of the two-sided rotatable mirror;
• wherein said third step defines an observation path for the at least one detecting light beam,
• wherein all of the steps of said method are performed so that the irradiation path and the observation path are spaced from each other at least at the system pupil.