Izvorni znanstveni članak
How to Convert the Obliquely Crossed to Non-Crossed Astigmatism? A Simple Method Using Vector Analysis
Božo Vojniković
; »Svjetlost« University Eye Clinic, Zagreb, Croatia
Nikica Gabrić
; »Svjetlost« University Eye Clinic, Zagreb, Croatia
Iva Dekaris
; »Svjetlost« University Eye Clinic, Zagreb, Croatia
Sažetak
The authors discussed about the problem of special form in astigmatism classification. This special type of astigmatism is the form of obliquely crossed astigmatism. In which the meridians, major and minor, are not right angles. In this astigmatism is not possible to prescribing for cylindrical (toric) spectacle lens. Authors describe the Thompson formula for oblique crossed cylinder and observe that this formula is to complicate for calculation new cylinder power. In this reason, the authors create the new formula and simple procedure for this calculation. This simple formula based on vector analysis and read: DM3 = DM2 ´ cos2 b.
Ključne riječi
obliquely crossed astigmatism; principal meridians; vector analysis
Hrčak ID:
102846
URI
Datum izdavanja:
22.4.2013.
Posjeta: 1.065 *