【Engineering Optics】Plane and Plane Systems

ref "Engineering Optics" 4th Edition Yu Daoyin

1. Types and functions of flat optical components

flat mirror

• The Simplest Optical Element for Perfect Imagery
  • The object image is symmetrical about a plane mirror
  • The image is the same size, the reality is opposite
  • The object is rotated, as if reversed by the same angle
• Mirror rotation $\angle \alpha$ , the ray turns$\angle 2\alpha \_$
• Small angle and displacement can be measured (optical lever)
  • 
  • $$F_{}F=2f^{\text{'}}\frac{x}{a}$$

parallel plate

• outgoing light // incoming light
• Can't zoom in or out
• Lateral axial displacement
• 
  • $$l{\_}^{\text{'}}=d(1-\frac{}{n})$$

Reflecting Prisms

• Function: Reversing the optical path, turning, inverting, scanning
• Classification
  • Simple Prisms: Dove Prism (Peripheral Sight), Schmidt Prism (Folded Optical Path)
  • Roof Prism: Even reflections
  • Cube Corners: Lateral Displacement
  • Compound Prisms: Beam splitting prisms (a beam of light is divided into two beams of equal optical path), dichroic prisms (color TV cameras), relay prisms (folded light path, telescopic system inverted image)
• expand
  • 
  • $$L=KD$$

Refractive Prism

• Function: deflects the beam direction, produces dispersion
• 
  • Refractive index measurement
  • $$\sin \frac{a+d_m}{2}=n\sin \frac{}{2}$$

light wedge

• 
  • $$d=a(n-1)$$
• Dual Wedge Rotation Micrometer
  • $$d=2\alpha (n-1)\cos Phi$$
• Double wedge moving micrometer
  • 
  • $$y\_=\Delta z\cdot d$$

Dispersion

The white light is decomposed into different colors after passing through the prism, and colorful lights are seen behind the prism

• The refractive index is large, the deflection angle is large
• The larger the Abbe number, the lower the dispersion
• White light spectrum: arranged in order of wavelength: red orange yellow green blue blue purple

Optical material

• Transmissive material
  • Optical glass, optical crystal, optical plastic
  • Optical properties are determined by transmittance and refractive index for each wavelength
  • The larger the Abbe number, the lower the dispersion
• Reflective material
  • no dispersion
  • Optical properties are determined only by spectral reflectance