Method and device for fitting toric contact lenses

A method for fitting a toric contact lens so as to determine a therapeutic axis based on a prescription axis, said method using a toric axis calculator including a card having a window therethrough, a first circular dial having a peripheral protractor scale with marking defining at least one counter-clockwise protractor scale of 0.degree. to 180.degree. about its periphery and being rotatably mounted on a rear face of the card so that the scale markings can be observed through the window as the dial is rotated, and a transparent circular dial including a reference symbol rotatably mounted on the front face of the card coaxially with the first circular dial, said method comprising:

• placing a test toric lens on a patient's eye, where said toric lens has an orientation mark at a known initial position;
• allowing the test toric lens to settle on the patient's eye so that the orientation mark rotates to a final position;
• rotating the first circular dial relative to the card, to position an angle on the protractor scale equal to the prescription axis with the window of the card;
• aligning the reference symbol on the transparent dial with the known initial position of the test lens orientation mark when the test lens is placed on the patient's eye;
• rotating the first circular dial and the transparent dial in unison, to bring the reference symbol to the final position of the orientation mark on the patient's eye;
• and
• reading the value of the therapeutic axis on the protractor scale through the window of the card.

A method for fitting a toric contact lens so as to determine an effective axis based on a prescription axis, said method using a toric axis calculator including a card having a window therethrough, a first circular dial having a peripheral protractor scale with markings defining at least one clockwise protractor scale of 0.degree. to 180.degree. about its periphery and being rotatably mounted on a rear face of the card so that the scale markings can be observed through the window as the dial is rotated, and a transparent dial including a reference symbol rotatably mounted on the front face of the card coaxially with the first circular dial, said method comprising:

• placing a test toric lens on a patient's eye, where said toric lens has an orientation mark at a known initial position;
• allowing the test toric lens to settle on the patient's eye so that the orientation mark rotates to a final position;
• rotating the first circular dial relative to the card to position an angle on the protractor scale equal to the prescription axis with the window of the card;
• aligning the reference symbol on the transparent dial with the final position of the orientation mark on the rotated test lens;
• rotating the first circular dial and the transparent dial in unison to align the reference symbol with the known initial position of the orientation mark of the test lens;
• and
• reading the value of the effective axis on the protractor scale through the window of the card.