Astigmatism testing apparatus and method of use

An optical testing apparatus for the determination of corrective prescriptions, comprising:

• a housing with a front wall and a rear wall held in a spaced configuration by at least one side wall, each front wall and rear wall;
• a first lens of a first cylindrical optical power;
• a second lens of a second cylindrical optical power;
• a first rotational unit with an angular scale indicating the rotary position of said first lens, said first rotational unit translationally fixed in said housing by a first set of stub axles that extend from said first rotational unit into hubs formed in said front wall and said rear wall;
• a second rotational unit with an angular scale indicating the rotary position of said second lens, said second rotational unit translationally fixed in said housing by a second stub axle that extends from said second rotational unit into said hubs;
• said first lens mechanically engaged with and constrained by said first rotational unit;
• said second lens mechanically engaged with and constrained by said second rotational unit;
• an optical axis passing through a center of said first lens along the direction of its cylindrical optical power and a center of said second lens along the direction of its cylindrical optical power wherein both said rotational units are independently motor driven and coaxially aligned about a common optical axis;
• a front viewing orifice in said front wall and a rear viewing orifice in said rear wall providing unobstructed view through said housing along said optical axis;
• a first rotational shaft operably connected to said first rotational unit to rotate said first lens;
• a second rotational shaft operably connected to said second rotational unit to rotate said second lens;
• a tactile input device capable of input in two degrees of freedom simultaneously, independently and with varying magnitude, said tactile input device providing a drive signal to a first motor coupled to said first rotational shaft for rotation, and providing a drive signal to a second motor coupled to said second rotational shaft for rotation;
• wherein said tactile input device is adapted to adjust or control the optical power of a combination of said first and second lenses by providing a first drive signal to said first motor and a second drive signal to said second motor to rotate said first lens and said second lens independently and simultaneously with real time synchronization between the position or the tactile input device and the optical characteristics of the combined system of said first and second lenses;
• wherein said rotary position indicated by said angular scale of said first lens and said rotary position indicated by said angular scale of said second lens when brought into focus by a patient, is convertible by said patient into an optical prescription.

An optometric apparatus for the measurement of astigmatism characteristics, comprising:

• a structural frame or support that has at least one rigid element;
• a first optical lens with first optical axis and a first toric refractive optical power or Jackson cross-cylinder refractive optical power in the direction of said first optical axis;
• a second optical lens with second optical axis and second toric refractive optical power or Jackson cross-cylinder refractive optical power in the direction of said second optical axis;
• wherein said first optical lens and said second optical lens are supported by said structural frame so as to prevent their translational motion or rotational motion except allowing the rotational motion of said first optical lens in the plane perpendicular to said first optical axis and allowing rotational motion of said second lens in the plane perpendicular to said second optical axis;
• and
• wherein said first optical lens and said second optical lens are spatially arranged so that there exists at least one straight line such that a light ray entering said optometric apparatus along that straight line would pass through both said first optical lens and said second optical lens and exit said optometric apparatus without being obstructed;
• a first actuator controllable by a first electrical signal, with said first actuator being engaged with said first optical lens and being capable of causing and controlling its rotational motion in the plain perpendicular to said first optical axis;
• a second actuator controllable by a second electrical signal, with said second actuator being engaged with said second optical lens and being capable of causing and controlling its rotational motion in the plain perpendicular to said second optical axis;
• a tactile sensor adapted to be directly operated by said patient, capable of receiving input via human manipulation performed concurrently in two or more independent degrees of freedom, such as translational motion, rotational motion, or any combination thereof, and capable of simultaneously generating said two independent first and second control signals based on said input;
• a microprocessor capable of receiving said control signals from said tactile sensor and sending electrical control signals to said first actuator and said second actuator simultaneously;
• a software program operating on said microprocessor;
• wherein said software program obtains said control signals from said tactile sensor, algorithmically processes said control signals, forms said first electrical signal and sends it to said first actuator, and forms said second electrical signal and sends it to said second actuator, simultaneously, independently of each other, and in real time, causing the combined optical characteristics of the system of said first and second lenses to be momentarily and continuously controlled by, and synchronized with, the position of the tactile sensor;
• and
• wherein said software program acquires a value of first angular position of said first optical lens by algorithmically processing a history of rotation of said first optical lens and acquires a value of second angular position of said second optical lens by algorithmically processing a history of rotation of said second optical lens, and
• wherein said software program algorithmically performs a calculation of optical parameters of the combined optical system comprised of said first optical lens and said second optical lens;
• an output communication device capable of providing, in human-readable or machine-readable form, quantitative results of said calculation of optical parameters of the combined optical system.