Manufacturing Tolerances - Apollo Optical

Tolerance	Description	Units	Injection Molding		Single Point Diamond Turning
Tolerance	Description	Units	Commercial	Precision	Commercial	Precision
Radius of Curvature	The radius of the optical surface	% of Radius of Curvature	±1%	±0.5%	±0.5%	±0.1%
Center Thickness	The thickness of the lens at the center	mm	±0.025	±0.015	±0.020	±0.005
Flange Diameter	The outside diameter of the lens	mm	±0.05	±0.025	±0.02	±0.005
Concentricity	Centering requirements typically refer to the position of one surface of a lens with respect to the second surface of the lens	mm	0.025	0.015	0.005	0.002
Edge Clearance	Edge clearance is the distance between the optical clear aperture and the physical outer dimensions of the part	mm	0.5	0.25	0.05	0.01
Surface Form (Spherical)	Power - maximum allowable deviation of the surface from its nominal shape based on an interferometer measurement	Fringes at 632.8 nm for 25mm diameter	10	4	4	2
Surface Form (Spherical)	Irregularity (localized departure from nominal) in fringes	Fringes at 632.8 nm for 25mm diameter	6	3	4	2
Cosmetics (Surface imperfection)	Surface imperfection tolerances and the scratch-dig specifications standard for optical components MIL-PRF-13830B	Scratch / Dig	60/40	40/20	60/40	40/20
Surface Roughness	Surface roughness or surface texture measures small scale irregularities on a surface	Å - RMS	<75	<50	<100	<75
Material imperfections	Material imperfections that may affect optical performance include stress birefringence, bubbles, inclusions, inhomogeneity, and striae. Due to the nature of manufacturing processes used for plastic optics, control of material imperfections is a challenge.
Surface treatment and coating	Optical coating specifications should include performance requirements expressed as a percentage of reflectance and/or transmission over a specific spectral range and range of angles of incidence.

Please keep in mind that many of these parameters will highly depend on the size, shape and material of the design part. These tolerances are meant as guidelines for design and should be reviewed with Apollo Optical's Design Team during the technical review process.