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AP130GT aspherized?

Started by Rick Keppler, 06/14/2011 11:42AM
Posted 06/14/2011 11:42AM Opening Post
I recently read that the AP130GT is not aspherized on one surface. Is this true? I thought all the oil spaced objectives AP130, AP140, AP155, AP180, etc had to be aspheric on one surface.
Posted 06/14/2011 02:21PM #1
To do an oil spaced ED triplet with zero color same as an airpaced
design like the AP 160EDF requires more than small aspheric work.
Right now there is no glass available that would allow all-spherical
or only small aspherics AND at the same time produce essentially zero
color error over the same spectrum as the 160EDF.


From the TEC newsgroup.