Precision Optics & Ultra-Precision Machining
SPDT Aspheric Lens & Tool Radius Calculator
Ultra-precision engineering calculator for optical fabricators, infrared lens machinists, and diamond turning programmers. Calculate even aspheric sagitta, tool center 2D offsets, and sub-nanometer surface finish parameters.
1. Input Parameters
Vertex radius R = 1/c: 10 - 100 mm.
Sphere (k=0), Parabola (k=-1), Ellipse (-1<k<0), Hyperbola (k<-1).
Clear optical aperture radius: 5 - 40 mm.
Single-crystal natural diamond nose radius: 0.10 - 1.50 mm.
Precision finishing cross feed: 0.5 - 3.0 μm/rev.
2. Calculation Results
Aspheric Vertex Sagitta (z_max)
3.12 mm
Theoretical Roughness (Rt)
0.56 nm
Max Normal Contact Angle (θ)
28.4°
Tool Center Offset (ΔX, ΔZ)
0.24, 0.06 mm
3. Dynamic Schematic & Tooling Guide
SPDT Aspheric Tooling Design Rules:
- Tool Nose Radius Compensation: Because the contact point shifts along the diamond nose arc as the surface slope theta varies, CAM toolpaths must offset tool center: X_cnc = r - R_tool*sin(theta), Z_cnc = z + R_tool*(1 - cos(theta)).
- Diffractive Phase Steps: Hybrid refractive-diffractive lenses require sharp vertical Fresnel zone transitions (< 0.5 μm dead zone) with controlled zero tool-clearance interference.
- Optical Materials: SPDT enables direct nanometer-level finishing (Ra < 2 nm) on Germanium, Silicon, ZnSe, PMMA, COP (Zeonex), and electroless nickel-plated mold inserts.