For this design, the aspheric surfaces were converted to Qcon surfaces, which are characterized by the sag departure of the aspheric surface from a base conic. This aspheric surface formulation gives designers a high level of control over the surface terms, which avoids unnecessary complications in fabrication and testing to reduce costs. CODE V has a straightforward process for converting aspheric surfaces to Qcon surfaces that maintains the surface shape.
In a smartphone camera system, the detector can be a source of ghost images because of the reflectivity of the metal wires in the sensor. Light reflecting off the detector structure can be returned to the detector by lens surfaces.
CODE V has powerful tools for analyzing ghost images, including:
- Ghost (GHO) analysis feature
- The supplied macro ghost_view.seq
- The @GHOST macro function
The Ghost analysis feature and the ghost_view macro provide data in tabular and visual formats. The analysis is fast and allows you to easily isolate surface pairs for further analysis or optimization control. The @GHOST macro function allows you to control for ghost image disk size during optimization by specifying a surface pair to control.
Following are examples of ghost_view reflections from a field angle of 2 degrees.