Lenses have many applications in range from the simple collection of the scanning of laser beams to precise imaging and image transferring. Lenses are classified as singlet, cylindrical, achromatic and ball lens according to the differentapplications.

Selecting the proper lens for your application requires making a number of choices. A few of the many considerations include: lens shape, conjugate ratio, f/number, transmission, wavefront distortion, scattered light, anti-reflection coating, and cost.

Singlet Lenses
These lenses are polished to tight tolerances using master test plates to ensure minimum wavefront distortion. Tight surface quality tolerances minimize scatter and unwanted diffraction effects. We have set up a special product line to produce small quantities of custom design optical components.

Plano-Convex Lens is best used where one conjugate point (object distance, S or image distance S') is more than five times the other. This lens shape is near best-form for either focusing collimated light or for collimating a point source.

Bi-Convex Lens is most suitable where the object and image are on opposite sides of the lens and the ratio of the image and object (conjugate ratio) distances is between 0.2 to 5.

Plano-Concave Lens has a negative focal length and is typically used to cause a collimated beam to diverge as in a Galilean type beam expander or Telescope. Because the spherical aberration of the Plano-Concave is negative, it can be used to balance the aberration of other lenses.

Bi-Concave Negative Lens is like the Plano-Concave lens in that it is used to produce divergent light. The Bi-Concave is best used when the input beam is converging.

Meniscus: The Positive Meniscus Lens can increase the NA of the system while only adding slightly to the total spherical aberrations. The Negative Meniscus Lens is used to increase the focal length of another lens while maintaining the angular resolution of the optical assembly. This lens shape is best used when one conjugate is relatively far from the lens.

Featured Material: For application in the visible and infrared up to about 2.1 μm, BK7 offers excellent performance at a good value. In the ultraviolet down to 195 nm, UV Fused Silica is a good choice. UV Fused Silica also has excellent transmission in the visible and infrared up to about 2.1 μm, better homogeneity, and a lower coefficient of thermal expansion than BK7. CaF2 and MgF2 offer high transmission in the deep UV, and they are excellent choices for deep UV excimer laser or infrared applications. Silicon and Germanium lenses are widely used in IR applications.

Optical surfaces requirements: The lens application drives the requirements for surface irregularity and surface quality.

Antireflection Coatings: We offer an extensive range of antireflection coatings covering the ultraviolet, visible, near infrared, and infrared regions. Please refer to our coatings chapter.

Diameter: We can make this lens from 1mm to 300mm. Also please reference to our testing glass when you do your design.

Lens Shapes:

Plano-Convex Lens	Bi-Convex Lens	Plano-Concave Lens
Bi-Concave lens	Positive Meniscus lens	Negative Meniscus lens

Doublets Lenses
When the optical aberrations of a system need to be controlled, this doublet is typically employed. Achromatic doublet lenses have significantly better optical performance than singlet lenses in visible imaging and laser beam manipulation applications. We always make our achromats as precise specifications and tolerances for uncompromising image quality upon customer’s requirement---Computer optimized designs minimize aberrations, yielding smaller focused spot sizes.

An Achromat consists of a positive low-index Crown Glass lens element cemented to a negative high-index Flint Glass lens element. The elements are chosen so as to cancel chromatic aberration at two well-separated wavelengths, usually in the blue and red region of the spectrum. Focal length is constant at those two wavelengths and focal length shifts are virtually eliminated across the visible wavelengths. One frequent use is to achieve diffraction limited focusing of a laser beam. Negative Achromats are typically used when there is a need to eliminate chromatic aberration. In addition to reducing chromatic aberration at the design wavelengths, spherical aberration and coma are greatly reduced.

Diameter: We can provide the cemented doublets of the diameter within 150mm.

Lens Shapes:

Positive Doublet Achromats	Negative Doublet Achromats

Lenses are the most regular components that Rising EO is making. We can reach very high quality but low price, and we can be competitive for any suppliers in the world. Rising EO processes thousands of radius Testing Plate for fabricating lenses in stock.

Manufacturing Tolerances

The general tolerance specifications above provide a guideline regarding manufacturing capabilities for optics ranging in size from 1-100mm. The manufacturing limits are not absolute; tighter tolerances may be possible. Part specific tolerances may vary depending on component size, shape, and/or material.