. 2006 Dec;104:437–452.

APPENDIX 2. TABLE A.

EYE MODEL PARAMETERS FOR THE DUAL-OPTIC INTRAOCULAR LENS (IOL)

MATRIX PARAMETERS	DEFINITION
First refraction surface = corneal surface K-reading	$R_{1} = K = \frac{337.5}{r_{1}}$ , where K = K-reading and r₁ = corneal radius^*
First interspace = anterior chamber depth (ACD)	t_1,n′ = aqueous refractive index (1.336)
Second refraction surface = power of front surface or conventional IOL or front surface of anterior lens of dual-optic IOL	$R_{2} = \frac{1000 \cdot (n_{a} - n^{'})}{r_{2}}$ , where n_a = refractive index of anterior lens material, n′ = aqueous refractive index (1.336) and r₂ = surface radius
Second interspace = anterior lens thickness or conventional lens thickness	t₂, n_a = refractive index of anterior lens material
Third refraction surface = power of back surface of conventional IOL or back surface of anterior lens of the dual-optic IOL	$R_{3} = \frac{- 1000 \cdot (n_{a} - n^{'})}{r_{3}}$ , where n_a = refractive index of anterior lens material, n′= aqueous refractive index (1.336) and r₂ = surface radius
Third interspace = separation between anterior and posterior lenses in the dual-optic IOL	t_3,n′ = aqueous refractive index (1.336)
Fourth refraction surface = power of front surface of posterior lens of the dual-optic IOL	$R_{4} = \frac{1000 \cdot (n_{p} - n^{'})}{r_{4}}$ , where n_p = refractive index of posterior lens material, n′ = aqueous refractive index (1.336) and r₄ = surface radius
Fourth interspace = posterior lens thickness	t₄, n_p = refractive index of posterior lens material
Fifth refraction surface = power of back surface of posterior lens of the dual-optic IOL	$R_{5} = \frac{- 1000 \cdot (n_{p} - n^{'})}{r_{5}}$ , where n_p = refractive index of anterior lens material, n′ = aqueous refractive index (1.336) and r₅ = surface radius

Radii are in millimeters with conventional optical science sign nomenclature. The light travels from left to right, and the sign is positive if it is along the ray direction and negative otherwise.