Measures of Source Intensity 1. Radiant Flux, Φ Rate of transfer of energy Φ = δQ/δt (W)

Measures of Source Intensity 2. Radiant Intensity, I Radiant flux per unit solid angle from a point source I = δΦ/δΩ (W/sr)

Measures of Source Intensity 3. Radiance, B Radiant flux per unit solid angle per unit projected area B = δ 2 Φ/(δΩ δA) (W sr -1 cm -1 )

Measures of Source Intensity 4. Irradiance, E Radiant flux per unit projected area E = δΦ/δA (W cm -1 )

Measures of Source Intensity 5. Spectral Radiance, B λ Radiance per unit wavelength interval B λ = B/δλ (W sr -1 cm -1 nm -1 )

Optical Components of Imaging Systems 1. Windows 2. Lenses 3. Mirrors 4. Turning Prisms 5. Beam Splitters 6. Fiber Optics

Transmittance of Window Materials

Reflectance of Mirror Materials

Interaction of Light with an Interface

Law of Specular Reflection Θ 1 = Θ 3 Snell’s Law of Refraction n 1 sin Θ 1 = n 2 sin Θ 2

Reflection Losses at an Interface (unpolarized light)

Reflection Losses at an Interface a = unpolarized b = perpendicularly polarized c = parallel polarized (Note Brewster’s Angle)

Reflection at an Interface (Total Internal Reflection) Propagating from high to low n

Total Internal Reflection n 1 sin Θ 1 = n 2 sin Θ 2 n 1 > n 2 Θ 2 = 90 sin Θ 1 = n 2 / n 1

Lens Maker’s Formula R 2 < 0 1/f = (n-1) (1/R 1 – 1/R 2 ) For a Biconvex Lens, R 1 = -R 2

Lens Formula 1/S1 + 1/S2 = 1/f S1 = object distance S2 = image distance f = focal length

1/S1 + 1/S2 = 1/f

Relative Aperture of an Optical Component D/S 1 where: D = limiting diameter S 1 = distance from source

F-number (F/n) F/n = S 1 /D The solid angle of light collected by an optical component is given by: Ω = (π/4) (F/n) -2

Beam Splitters

Optical Fibers

Turning Prisms

Sample Cells