Lenslet Array 1
The array aspects of this object are provided for back compatibility with older versions of OpticStudio. A more efficient method that ray-traces more quickly is to make a single lenslet and then create an array using the Array Object - see " Array " for details.
A Lenslet Array 1 object consists of an array of rectangular volumes, each with a flat front face and a curved back face. The back face may be plane, sphere, conic, or polynomial asphere; or a spherical, conic, or polynomial aspheric toroid. The shape may be decentered with respect to the center of the lenslet. A toroidal surface is defined by a curve in the YZ plane which is then rotated about an axis parallel to the Y axis but displaced by a distance R; called the radius of rotation.
If the back face is rotationally symmetric, the radial profile is defined by a sag expression identical to the Even Asphere surface:
If the back face is a toric, then the profile is described by an identical expression in the y coordinate alone:
where c is the reciprocal of the radius of curvature in YZ plane.
Either the front or the back surface may be a diffraction grating. The grating is assumed to consist of equally spaced lines parallel to the local x axis. The grating frequency is the lines per micrometer along the y direction; projected down on to the surface.
The Lenslet Array 1 is defined by these parameters:
| Parameter # | Description | Face Name | Face # |
| 1 | The X Half-Width in lens units of each lenslet. | NA | NA |
| 2 | The Y Half-Width in lens units of each lenslet. | NA | NA |
| 3 | The thickness along the local Z axis of each lenslet. | Side | 0 |
| 4-5 | Unused. | NA | NA |
| 6 | The radius of curvature of each lenslet, use zero for a plane. | Back | 2 |
| 7 | The conic constant of each lenslet. | Back | 2 |
| 8 | The "Is Toric" flag; if zero the lenslet surface is rotationally symmetric, otherwise it is toroidal. | Back | 2 |
| 9 | The radius of rotation of each lenslet if the lenslet surface is toric. | Back | 2 |
| 10 | The grating line frequency in lines/micrometer on either the front or back face, see parameter 24. | NA | NA |
| 11 | The diffraction order. Multiple orders may be specified, see "Diffraction tab" . | NA | NA |
| 12-19 | The aspheric coefficients 1-8. | Back | 2 |
| 20-21 | The decenter x and decenter y of the curved back face. | Back | 2 |
| 22-23 | The number of lenslet elements in x and y. If the total number of lenslets is large, it is generally much faster to use a single lenslet (set parameters 22 and 23 both equal to 1) and then use the Array object to create the array of lenslets. The Array object method is much more powerful, uses less memory, and will generally load and trace much faster than using a large number of lenslet elements. See "Array" . | Back | 2 |
| 24 | The face to make diffractive. This value must be 1 (front face) or 2 (back face). | NA | NA |
Note a cylinder lens results if the radius of rotation is set to zero. The reference coordinate is the center of the front face. Face Numbers: Outside edge side faces are Face 0, flat front face Face 1, curved back face Face 2, inside side faces Face 3 (these are the side faces formed in the interior of an array of lenslets when decentered lens faces meet).
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