Optical mapping apparatus with adjustable depth resolution and multiple functionality

An optical mapping apparatus which comprises an optical radiation source made out of two optical sources of different wavelengths which are combined by a fiber directional single mode coupler or a bulk beam-splitter;

• a confocal optical receiver with or without adjustable depth resolution;
• an optical splitter, shared by the optical source and the confocal optical receiver, to direct some of the light returned from an object situated at the object location to the optical confocal optical receiver, where the optical-splitter is used by the source in reflection and by the confocal channel in transmission, regime called R-S/T-C and it is equally possible for the optical-splitter to be used in transmission by the source and in reflection by the confocal channel, regime called TS-S/R-C;
• transverse scanning means consisting of a line scanner and a frame scanner, to effect transverse scanning of an optical output from the optical splitter over a line or a predetermined area in the object;
• interface optics for transferring an optical beam from the transverse scanning means to the object and for transferring an optical output beam reflected and scattered from the object back to the optical-splitter through the transverse scanning means, and from the optical-splitter to the confocal optical receiver of the confocal channel in a ratio determined by the optical splitter and the wavelength backscattered or emitted by the object;
• optionally, a fixation lamp for sending light from an external source towards the object;
• optionally, an interface optics-splitter shared by the light of the fixation lamp beam and the imaging beam;
• focusing adjustment means placed between the optical-splitter and the transverse scanning means, to vary the position of the focused beam in the object;
• analysing means, for demodulating the photodetected signals of the photodetectors in the confocal optical receiver;
• depth adjustment means for altering the focus, over a predetermined amount for at least one point in a raster in either steps or continuously at a pace synchronised with the focusing adjustment, according to a synchronising procedure;
• displaying means for generating and processing the images created by the confocal optical receivers, and;
• timing means which controls the 3D scanning operation regime, when the mapping apparatus acquires en-face images in a plane perpendicular on the optic axis (or in the patient face) at different focusing depths, where the optic axis is an imaginary axis from the scanning means through the interface optics to the object.

An optical mapping apparatus which comprises:

• an optical coherence tomography (OCT) system built around an in-fiber or a bulk interferometer excited by an optical radiation source;
• transverse scanning means to effect transverse scanning of the object using an optical output from the optical splitter (as an imaging beam), over a line or a predetermined area in the object;
• interface optics for transferring an optical beam from the transverse scanning means to the object, and for transferring an optical output beam reflected and scattered from the object back to the OCT system;
• optionally a fixation lamp for sending light from an external source towards the object;
• optionally, an interface optics-splitter shared by the optional fixation lamp beam and the imaging beam, wherein the interface optics-splitter can be used either in reflection or transmission by the imaging beam, while the fixation lamp beam is transmitted or reflected, respectively;
• focusing adjustment means placed between the output of the OCT system and the transverse scanning means, to maintain the input aperture of the interferometer in focus, while focusing the scanned beam on the object;
• optionally means to introduce intensity or phase modulation or intensity modulation and phase modulation in the OCT interferometer;
• analysing means, coupled to the transverse scanning means, for demodulating the photodetected signals of the photodetectors in the interferometer;
• depth adjustment means for altering the optical path difference in said OCT interferometer over a predetermined amount for at least one point in the transverse scanning means in either steps or continuously at a pace synchronised with the focusing adjustment means, according to a synchronising procedure;
• displaying means for generating and processing the image created by the interferometer;
• optionally timing means which control two main operation regimes, namely (i) en-face imaging when the mapping apparatus acquires transverse images at constant depth in a perpendicular plane to the optic axis and (ii) longitudinal imaging when the mapping apparatus acquires longitudinal images, in a parallel plane to the optic axis, where the optic axis is an imaginary axis from the scanning means through the interface optics to the object.