A cylindrical lens contains an optical surface that has a radius in one direction and is flat in the orthogonal direction. A cylinder will have one or more cylindrical surfaces with differing radii. Cylindrical optics are used in medical instruments, graphic arts, laser printers, and semiconductor processing equipment.
We’ll walk you through the process, and invite you to visit the Resource Library for technical resources at every step.
Specifying a cylindrical optic begins with the cylinder radius and includes a tolerance for the radius (power) axis as well as the plano (zero power) axis. Irregularity and slope may also be defined. Decentration or wedges in both axes should be specified, as well as the alignment of the optical axis with the mechanical axis. Plano or spherical surfaces should have tolerances similar to any plano or spherical surface.
Optimax makes cylinders from optical materials such as glass, fused silica, crystals and ceramics for UV, Visible and IR applications using proprietary “grind and shine” techniques to produce low scatter surfaces. Optimax utilizes deterministic CNC machine tools for predictable removal rates and adherence to tight tolerances. To control centration, precision tools constrain the optical axis.
For more information please see:
Rod or Arbor |
||
|---|---|---|
Attribute |
Minimum |
Maximum |
| Length (mm) | 3 | 5001 |
| Width (mm) Radius dependent | 2 | < 2x Radius |
| Cylinder Radius (mm) – Convex Only | 2 | 150 |
X-Y |
||
| Attribute | Minimum | Maximum |
| Length (mm) | 3 | 300 |
| Width (mm) | 2 | 300 |
| Cylinder Radius (mm) | 10 | ∞ |
| Concave sag to flat (mm) | 0.1002 | =Radius |
Based on Form Error Tolerance
Form Error > 2μm Lower Resolution Profilometry (2-D)1 |
||
|---|---|---|
Attribute |
Minimum |
Maximum |
| Diameter (mm) | 3 | 250 |
| Local Radius (mm) | -8 (Concave) | ∞ |
| Sag (mm) | 0 | 502 |
| Departure (mm) | 0.01 | 20 |
| Included Angle (°) | 0 | 120 |
Form Error 0.5 – 2μm Higher Resolution Profilometry (2-D)1 |
||
Attribute |
Minimum |
Maximum |
| Diameter (mm)3 | 3 | 250 |
| Local Radius (mm) | -12 (Concave) | ∞ |
| Sag (mm) | 0 | 252 |
| Departure (mm) | 0.01 | 20 |
| Included Angle (°) | 0 | 150 |
Form Error < 0.5μm Interferometry with Stitching (3-D) |
||
Attribute |
Minimum |
Maximum |
| Diameter (mm)3 | 3 | 250 |
| Local Radius (mm) | -13 (Concave) | ∞ |
| Sag (mm) | 0 | 252,4 |
| Departure (mm) | 0.002 | 1 |
| Included Angle (°) | 0 | 120+5 |
Attribute |
Minimum |
Maximum |
| Diameter | 3mm | 500mm |
| Wavelength | 193nm | 6000nm |
| Use Environment | Vacuum | >95% RH |
| Durability | Moderate abrasion | Severe abrasion |
| Measurement | — | 68°, s, p, average polarization |
| Laser Damage Threshold | — | 1064nm: >30J/cm2@10ns, >1MW/cm2CW |
| Layers | 1 | 200 |
Attribute |
Tolerancing Limit* |
| Diameter (mm) | +0, -0.010 |
| Center Thickness (mm) | ± 0.050 |
| Irregularity – Interferometry (HeNe fringes) |
0.1** |
| Irregularity – Profilometry (μm) | ±1.0 |
| Wedge Lens – ETD (mm) |
TBD |
| Surface Roughness (Å RMS) | 10 |
Attribute |
Minimum |
Maximum |
| Diameter (mm) | 3 | 300 |
| Thickness | 1 | 150 |
| Aspect Ratio1 | 1 | 502 |
Based on Form Error Tolerance
Attribute |
Minimum |
Maximum |
| Diameter (mm) | 3 | 400 |
| Radius (mm) | ±1 | ∞2 |
| Aspect Ratio (Diameter/Center Thickness) | <1:1 | 30:1 |
| Included Angle (°) | 0 | 2103 |
Attribute |
Cylinder Tolerancing Limit |
|---|---|
| Glass Quality (nd, vd) | Melt Rebalanced and Controlled |
| Length and width (mm) | +0, -0.020 |
| Center Thickness (mm)3 | ± 0.020 |
| Sag – Concave (mm) | ± 0.020 |
| Clear Aperture | 100%4 |
| Radius5 | ± 0.1% or 3 HeNe fringes6 |
| Irregularity – Interferometry (HeNe fringes)7 | 0.18 |
| Irregularity – Profilometry (μm) | ± 0.5 |
| Plano Axis Wedge – ETD (mm) | 0.00512 |
| Cylinder Axis Decentration – TIR (mm)9 | 0.01010 |
| Axial Twist Angle (arcminutes) | 3 |
| Bevels – Face Width @ 45° (mm)11 | 0/0mm max |
| Scratch – Dig (MIL-PRF-13830B)12 | 10 – 5 |
| Surface Roughness (Å RMS)13 | 5 |
Attribute |
Prism Tolerancing Limit |
|---|---|
| Glass Quality (nd, vd) | Melt Rebalanced and Controlled |
| Diameter (mm) | +0, -0.010 |
| Center Thickness (mm)3 | ± 0.010 |
| Sag – Concave (mm) | ± 0.010 |
| Clear Aperture | 100%4 |
| Power5 | 0.1 HeNe fringes6 |
| Irregularity – Interferometry (HeNe fringes)7 | 0.18 |
| Wedge Prism (window) – ETD (mm)9 | 0.00210 |
| Bevels – Face Width @ 45° (mm)11 | sharp |
| Scratch – Dig (MIL-PRF-13830B)12 | 10 – 5 |
| Surface Roughness (Å RMS)13 | 4 |
Attribute |
Asphere Tolerancing Limit |
|---|---|
| Glass Quality (nd, vd) | Melt Rebalanced and Controlled |
| Diameter (mm) | +0, -0.010 |
| Center Thickness (mm)6 | ± 0.010 |
| Sag – Concave (mm) | ± 0.010 |
| Clear Aperture | 100%7 |
| Vertex Radius8 | ± 0.1% or 3 HeNe fringes9 |
| Irregularity – Interferometry (HeNe fringes)10 | 0.111 |
| Irregularity – Profilometry (μm)10 | ± 0.5 |
| Wedge Lens – ETD (mm) | 0.00212 |
| Bevels – Face Width @ 45° (mm)13 | ± 0.05 |
| Scratch – Dig (MIL-PRF-13830B)14 | 10 – 5 |
| Surface Roughness (Å RMS)15 | 10 |
Attribute |
Sphere Tolerancing Limit |
|---|---|
| Glass Quality (nd, vd) | Melt Rebalanced and Controlled |
| Diameter (mm) | +0, -0.010 |
| Center Thickness (mm)4 | ± 0.020 |
| Sag – Concave (mm) | ± 0.010 |
| Clear Aperture | 100%5 |
| Radius (mm)6 | ± 0.0025 or 1 HeNe fringe7 |
| Irregularity (HeNe fringes)8 | 0.059 |
| Wedge Lens – ETD (mm) | 0.00210 |
| Bevels – Face Width @ 45° (mm) | ± 0.0511 |
| Scratch – Dig (MIL-PRF-13830B)12 | <10 – 5 |
| Surface Roughness (Å RMS) | 313,14 |
Here are manufacturing limits and tolerances specific to optical aspheres, prisms, cylinders and spheres. For more detailed information on any attribute, please contact sales@optimaxsi.com.
Optimax uses interferometric techniques to verify the plano axis and power axis of the optic. These techniques include plano reference flats, Distance Measuring Interferometry and CGH diffractive elements. Mechanical attributes such as wedge are verified with micrometers or by optical methods.
A CGH diffractive null converts the plane wavefront from a transmission flat to a cylindrical wavefront. This can be used to measure convex or concave surfaces. Available coverage varies greatly based on the size and shape of the cylindrical surface.
For more information on CGH nulls and an illustration of available coverage please see:
Optimax’s R&D department is continuously looking for ways to improve our fabrication process and produce higher quality optics. Our current research projects are designed to meet future market needs, such as:
For more information please see Optimax Innovation or contact sales@optimaxsi.com.
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