Equations and corresponding legends for each of our EO Tech Tools.
Focal Length
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
| ΦOS | Power of Surface 1 |
| ΦIS | Power of Surface 2 |
| Φ | Lens Power |
| nOS | Object Space Index |
| nL | Lens Index |
| nIS | Image Space Index |
| R1 | Radius of Surface 1 |
| R2 | Radius of Surface 2 |
| CT | Center Thickness |
| P | Primary Principle Point |
| P' | Secondary Principle Point |
| EFL | Effective Focal Length |
| BFL | Back Focal Length |
| FFL | Front Focal Length |
| NPS | Nodal Point Shift |
| fF | Front Focal Point |
| fR | Rear Focal Point |
Gaussian Beam
(12)
(13)
(14)
(15)
(16)
(17)
| λ | Wavelength |
| zR | Rayleigh Range |
| z | Axial Distance |
| ω(z) | Half Beam Diameter |
| ω0 | Beam Waist |
| b | Confocal Parameter |
| ωR | Rayleigh Half Diameter |
| R(z) | Radius of Curvature |
| θ | Half Angle Divergence |
Koehler Illumination
(18)
(19)
(20)
(21)
(22)
(23)
(24)
| d1 | Source to Lens 1 Distance |
| d2 | Lens 1 to Lens 2 Distance |
| d3 | Lens 2 to Spot Diameter Distance |
| DL1 | Diameter of Lens 1 |
| DL2 | Diameter of Lens 2 |
| FL1 | Focal Length of Lens 1 |
| FL2 | Focal Length of Lens 2 |
| Dsource | Source Diameter |
| Dspot | Spot Diameter |
| NAinput | Input Numerical Aperture |
| NAoutput | Output Numerical Aperture |
Laser Spot Size
(25)
| DI | Input Beam Diameter |
| DO | Output Beam Diameter |
| θI | Beam Divergence |
| L | Working Distance |
1951 USAF
(26)
SAG
(27)
| R | Radius of Curvature |
| D | Diameter |
Simply Magnifier
(28)
(29)
| MP | Magnifying Power |
| FL | Focal Length |