TY - JOUR
T1 - An optical system with continuously variable spherocylindrical power
AU - Guyton, David L.
AU - Crane, Hewitt D.
N1 - Funding Information:
The system described in this paper was developed in 1969 and patented by Dr. Guyton (U.S. Patent No. 3,664,631). The American Optical Corporation is currently marketing instruments incorporating the system. The same system was devised later, and independently, by the second author.
PY - 1978/8/8
Y1 - 1978/8/8
N2 - Conventional instruments for measuring or correcting refractive errors of the human eye contain large numbers of individual spherical and cylindrical lenses. Refracting instruments having continuously variable power (optometers) are mechanically simpler and allow smooth adjustment of power by the subject (subjective optometers) or smooth adjustment of power by automated photo-electronic sensing mechanisms (objective optometers). Optometers with spherical optical systems have had some clinical success, but those with spherocylindrical optical systems, described since the 1800's, have never been practically useful. Power ranges have been too small, scales have been non-linear, and adjustments have been awkward. Renewed interest in the automation of clinical refraction has led to the development of a spherocylindrical optical system overcoming the disadvantages of previous systems. Cylindrical lenses movable in a prescribed fashion along the optical axis provide continuously variable spherocylindrical power over a wide linear range. This system, in addition to forming the basis of a new refracting instrument, may provide a useful means for manipulation of spherocylindrical power in other optical applications.
AB - Conventional instruments for measuring or correcting refractive errors of the human eye contain large numbers of individual spherical and cylindrical lenses. Refracting instruments having continuously variable power (optometers) are mechanically simpler and allow smooth adjustment of power by the subject (subjective optometers) or smooth adjustment of power by automated photo-electronic sensing mechanisms (objective optometers). Optometers with spherical optical systems have had some clinical success, but those with spherocylindrical optical systems, described since the 1800's, have never been practically useful. Power ranges have been too small, scales have been non-linear, and adjustments have been awkward. Renewed interest in the automation of clinical refraction has led to the development of a spherocylindrical optical system overcoming the disadvantages of previous systems. Cylindrical lenses movable in a prescribed fashion along the optical axis provide continuously variable spherocylindrical power over a wide linear range. This system, in addition to forming the basis of a new refracting instrument, may provide a useful means for manipulation of spherocylindrical power in other optical applications.
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U2 - 10.1117/12.956509
DO - 10.1117/12.956509
M3 - Article
AN - SCOPUS:0018109052
SN - 0277-786X
VL - 141
SP - 26
EP - 30
JO - Proceedings of SPIE - The International Society for Optical Engineering
JF - Proceedings of SPIE - The International Society for Optical Engineering
ER -