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Three-element zoom lens with fixed distance between focal points
Antonin Mikš1, Jiří Novák, Pavel Novák
1Czech Technical University in Prague, Faculty of Civil Engineering, Department of Physics, Thakurova 7, 16629 Prague, Czech Republic. miks@fsv.cvut.cz
Optics Letters
|June 29, 2012
Summary
This study analyzes zoom lenses with fixed focal distances, deriving equations for three-element designs. The analysis confirms that more than two optical elements are necessary for such zoom lens systems.
Area of Science:
- Optical engineering
- Lens design
Background:
- Zoom lenses are crucial optical instruments.
- Fixed focal distance designs present unique challenges.
Purpose of the Study:
- To theoretically analyze zoom lenses with a fixed distance between focal points.
- To derive paraxial design equations for a three-element zoom lens.
Main Methods:
- Theoretical analysis.
- Derivation of equations for primary (paraxial) design parameters.
Main Results:
- Established equations for the basic parameters of a three-element zoom lens.
- Demonstrated that a minimum of three optical elements is required.
Conclusions:
- A theoretical framework for fixed focal distance zoom lenses was developed.
- The minimum element count for this type of zoom lens is three, not two.
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