Apparatus for formation of an ophthalmic lens precursor and lens
This invention discloses apparatus for generating an ophthalmic lens with at least a portion of one surface free-formed from a Reactive Mixture. In some embodiments, an ophthalmic lens is formed on a substrate with an arcuate optical quality surface via a source of actinic radiation controllable to cure a definable portion of a volume of Reactive Mixture.
1. An apparatus for forming an ophthalmic Lens Precursor, the apparatus comprising:
a lens precursor forming substrate comprising a convex optical quality surface; and,
wherein the convex optical quality surface is positioned into a vessel, wherein the vessel contains a volume of a Reactive Mixture that exceeds the volume of the formed Lens Precursor and the shape of the vessel does not influence the shape of the lens precursor;
a source of actinic radiation controllable to cure one or more voxels of said single volume of Reactive Mixture, said source of actinic radiation comprising a light beam source and a digital mirror device; and
said digital mirror device capable of dividing a light beam into multiple pixels of light, wherein discrete pixels may be directed to an ON path and an OFF path, wherein the ON path is directed through the optical quality convex surface in a predefined pattern on a voxel by voxel basis wherein a duration of respective ON path directions of the light beam on a voxel by voxel basis is controllable to control a depth of polymerization of respective Voxels.
2. The apparatus for forming an ophthalmic Lens Precursor of claim 1 , wherein the source of actinic radiation includes a light source and the apparatus further includes:
a homogenizer positioned to receive light from the light source and providing the light with more uniform intensity than the light received and wherein the light with more uniform intensity includes the actinic radiation.
3. The apparatus for forming an ophthalmic Lens Precursor of claim 2 , wherein the apparatus further includes a spatial light modulator reflecting at least a portion of the light provided by the homogenizer.
4. The apparatus for forming an ophthalmic Lens Precursor of claim 3 , wherein the apparatus further includes optics for converging light reflected by the spatial light modulator.
5. The apparatus for forming an ophthalmic Lens Precursor of claim 4 , wherein the substrate includes a mold part comprising a lens forming surface at least partially transmissive to the actinic radiation, wherein the mold part is positioned to receive the actinic radiation from the converging lens system.
6. The apparatus for forming an ophthalmic Lens Precursor of claim 1 additionally comprising a source of fixing radiation.
7. The apparatus of claim 2 wherein the homogenizer includes a collimator homogenizer.
8. The apparatus of claim 1 wherein the thickness of a voxel X thick at a given x,y coordinate on the arcuate surface is based upon one or more of an intensity I, a wavelength, and an exposure time t of the light beam directed at the voxel correlating with the x,y coordinate.
9. The apparatus of claim 8 wherein thickness of the x,y voxel is based upon the formula: x Thick (x, y)=f(I 0 (x,y),t(x,y)).