Ophthalmoscopes

A computer readable non-transitory media storing program instructions which, when executed, perform a method of determining a correction for distortion in eye representations of an ophthalmoscope by:

• (i) constructing a digital model of an optical system comprising the ophthalmoscope and a model eye,
• (ii) transmitting the digital model of the optical system to a ray tracing system and passing a ray through the optical system onto a surface of the model eye of the digital model,
• (iii) calculating a first measurement, with distortion, of the ray at the surface of the model eye,
• (iv) determining an angular position of a horizontal scanning element of the ophthalmoscope used to produce the ray and an angular position of a vertical scanning element of the ophthalmoscope used to produce the ray,
• (v) determining a horizontal scanning angle of the optical system and a vertical scanning angle of the optical system for the ray based on the angular position of the horizontal scanning element and the angular position of the vertical scanning element,
• (vi) calculating a second measurement, without distortion, of the ray at the surface of the model eye using the horizontal scanning angle of the optical system and vertical scanning angle of the optical system, and
• (vii) comparing the first measurement, with distortion, of the ray at the surface of the model eye with the corresponding second measurement, without distortion, of the ray at the surface of the model eye to determine the correction for distortion in eye representations of the ophthalmoscope.

A method of correcting distortion in an eye representation acquired using an ophthalmoscope comprising:

• obtaining a correction for distortion in eye representations of the ophthalmoscope by:
• (i) constructing a digital model of an optical system comprising the ophthalmoscope and a model eye,
• (ii) transmitting the digital model of the optical system to a ray tracing system and passing a ray through the optical system onto a surface of the model eye of the digital model,
• (iii) calculating a first measurement, with distortion, of the ray at the surface of the model eye,
• (iv) determining an angular position of a horizontal scanning element of the ophthalmoscope used to produce the ray and an angular position of a vertical scanning element of the ophthalmoscope used to produce the ray,
• (v) determining a horizontal scanning angle of the optical system and a vertical scanning angle of the optical system for the ray based on the angular position of the horizontal scanning element and the angular position of the vertical scanning element,
• (vi) calculating a second measurement, without distortion, of the ray at the surface of the model eye using the horizontal scanning angle of the optical system and vertical scanning angle of the optical system,
• (vii) comparing the first measurement, with distortion, of the ray at the surface of the model eye with the corresponding second measurement, without distortion, of the ray at the surface of the model eye to determine the correction for distortion in eye representations of the ophthalmoscope;
• and
• using the correction to map points of the acquired eye representation to corresponding points of a corrected eye representation.

A computer readable non-transitory media storing program instructions which, when executed, perform a method of correcting distortion in an eye representation acquired using an ophthalmoscope by:

• obtaining a correction for distortion in eye representations of the ophthalmoscope by:
• (i) constructing a digital model of an optical system comprising the ophthalmoscope and a model eye,
• (ii) transmitting the digital model of the optical system to a ray tracing system and passing a ray through the optical system onto a surface of the model eye of the digital model,
• (iii) calculating a first measurement, with distortion, of the ray at the surface of the model eye,
• (iv) determining an angular position of a horizontal scanning element of the ophthalmoscope used to produce the ray and an angular position of a vertical scanning element of the ophthalmoscope used to produce the ray,
• (v) determining a horizontal scanning angle of the optical system and a vertical scanning angle of the optical system for the ray based on the angular position of the horizontal scanning element and the angular position of the vertical scanning element,
• (vi) calculating a second measurement, without distortion, of the ray at the surface of the model eye using the horizontal scanning angle of the optical system and vertical scanning angle of the optical system,
• (vii) comparing the first measurement, with distortion, of the ray at the surface of the model eye with the corresponding second measurement, without distortion, of the ray at the surface of the model eye to determine the correction for distortion in eye representations of the ophthalmoscope;
• and
• using the correction to map points of the acquired eye representation to corresponding points of a corrected eye representation.

An ophthalmoscope comprising a computer readable non-transitory media storing program instructions which, when executed, perform a method of determining a correction for distortion in eye representations of an ophthalmoscope by:

• (i) constructing a digital model of an optical system comprising the ophthalmoscope and a model eye,
• (ii) transmitting the digital model of the optical system to a ray tracing system and passing a ray through the optical system onto a surface of the model eye of the digital model,
• (iii) calculating a first measurement, with distortion, of the ray at the surface of the model eye,
• (iv) determining an angular position of a horizontal scanning element of the ophthalmoscope used to produce the ray and an angular position of a vertical scanning element of the ophthalmoscope used to produce the ray,
• (v) determining a horizontal scanning angle of the optical system and a vertical scanning angle of the optical system for the ray based on the angular position of the horizontal scanning element and the angular position of the vertical scanning element,
• (vi) calculating a second measurement, without distortion, of the ray at the surface of the model eye using the horizontal scanning angle of the optical system and vertical scanning angle of the optical system,
• (vii) comparing the first measurement, with distortion, of the ray at the surface of the model eye with the corresponding second measurement, without distortion, of the ray at the surface of the model eye to determine the correction for distortion in eye representations of the ophthalmoscope.

An ophthalmoscope comprising a computer readable non-transitory media storing program instructions which, when executed, perform a method of correcting distortion in an eye representation acquired using an ophthalmoscope by:

• obtaining a correction for distortion in eye representations of the ophthalmoscope by:
• (i) constructing a digital model of an optical system comprising the ophthalmoscope and a model eye,
• (ii) transmitting the digital model of the optical system to a ray tracing system and passing a ray through the optical system onto a surface of the model eye of the digital model,
• (iii) calculating a first measurement, with distortion, of the ray at the surface of the model eye,
• (iv) determining an angular position of a horizontal scanning element of the ophthalmoscope used to produce the ray and an angular position of a vertical scanning element of the ophthalmoscope used to produce the ray,
• (v) determining a horizontal scanning angle of the optical system and a vertical scanning angle of the optical system for the ray based on the angular position of the horizontal scanning element and the angular position of the vertical scanning element,
• (vi) calculating a second measurement, without distortion, of the ray at the surface of the model eye using the horizontal scanning angle of the optical system and vertical scanning angle of the optical system,
• (vii) comparing the first measurement, with distortion, of the ray at the surface of the model eye with the corresponding second measurement, without distortion, of the ray at the surface of the model eye to determine the correction for distortion in eye representations of the ophthalmoscope;
• and
• using the correction to map points of the acquired eye representation to corresponding points of a corrected eye representation.