Classic Optical Designs: Double-Gauss, Sonnar to Fluorite APO Evolution

Content to be added - This article will trace the evolution of fundamental lens optical formulas.

Article Outline

1. Historical Development Timeline

• Early lens design evolution
• Key patent milestones
• Manufacturer innovations
• Design family relationships

2. Classic Design Analysis

• Double-Gauss symmetrical design
• Sonnar telephoto formula
• Planar wide-angle approach
• Retrofocus design principles
• APO achromatic implementation

3. Aberration Correction Methods

• Spherical aberration control
• Chromatic aberration reduction
• Coma and astigmatism minimization
• Field curvature correction
• Distortion management

4. Modern Applications

• Contemporary lens implementations
• Digital sensor optimizations
• Computational corrections
• Future design directions

This article structure is ready for in-depth content development.