Design Innovation

Sunex is a pioneer in developing innovative optics for digital imaging applications.  Over the years we have developed an extensive library of proprietary lens designs that optimize the performance of digital imaging systems. To deliver the best value to our customers,  we strive to achieve the best overall balance between performance, size, cost and manufacturability. Examples of our innovative designs include:

Miniature Fisheye Lenses

Traditional fisheye lenses are bulky and expensive to manufacture.  Furthermore, their performance are limited by the poor off-axis resolution and chromatic aberrations. In response to these shortcomings, we created a series of miniature fisheye lenses using specially formulated high-index materials. Our miniature fisheye lenses are a fraction of the size and weight of other fisheye lenses.  They provide excellent off-axis imaging quality with minimal amount of chromatic aberrations.  Because of this innovative design approach, we are able to offer these lenses at drastic lower prices than other fisheye lenses. This technology has enabled our customers to develop a range of new cameras taking advantage of the low-cost multi-megapixel CMOS imagers.

Tailored Distortion®:  Distortion Correction at Speed of Light

Super wide-angle lenses and fisheye lenses have pronounced barrel distortion. When viewing a flat object, off-axis features are "squeezed" significantly relative to the on-axis ones.  This reduces the effective off-axis resolutions. For many applications,  it is an undesirable effect. It is possible to post-processing the image to reduce this effect.  However post-processing in software reduces the image quality because the missing off-axis information must now be interpreted. We created a new class of super wide-angle and fisheye designs using high precision aspherical elements to reduce the off-axis "squeezing" optically.  Comparing with standard f-theta designs, the distortion reduction is on the order of 50%. This allows off-axis objects to be imaged with more pixels.  This technology has brought significant commercial benefits to security and automotive back-up cameras.

Tailored distortion lenses for security applications

Like a traditional fisheye lens, Tailored Distortiontion™ is ideal for security applications where an ultra-wide field of view is required. Tailored Distortion offers some key advantages over a traditional fisheye, however. This is true particularly for 360º surveillance cameras or in applications where post-processing or dewarping of the image is either unneeded or undesirable. The reason for this is two-fold. First, traditional fisheye lenses suffer from compression of the image at the edges. Since there is simply more area to cover at the periphery of the imaged area, the edge of the image becomes compressed, with less pixels available per unit area. This can be a critical issue for 360º imaging applications, since the areas of interest are usually located at the edges of the image (see example below). Tailored Distortion largely solves this situation by intentionally compressing the center of the image, leaving more pixels available at the edge. This results in high resolution throughout the image. Tailored Distortion lenses also behave in a predictable way, so that post-dewarping is still an option, and in fact delivers more uniform and higher resolution across the entire image than a comparable, traditional fisheye lens. The second primary advantage of Tailored Distortion is that it provides a more rectilinear image. The result is an image that maintains a more realistic perspective that is much less disorienting than traditional fisheye images. This means that many applications, such as doorbell phones or 360º surveillance may not require any software dewarping at all. And since Tailored Distortion is all done optically, there is no software manipulation of the actual image, thus avoiding many of the issues sometimes associated with post-processing.

Automotive applications:

The following is a comparison between two backup camera lenses.  The technical advantage of Tailored Distortion is clear.

Rear view camera with standard lens	Rear view camera with a Tailored Distortion™ lens

Boresight Stablization

A typical lens assembly consists of several lens elements inside a cylindrical barrel.  Due to the mechanical clearance requirement, the internal element diameters must be smaller than the barrel internal diameter.  This creates the potential risk that the elements may shift laterally under strenuous conditions thus causing a shift in the lens bore sight.  This risk can be devastating for certain applications. To eliminate this risk, we have created an opto-mechanical design process that allows us evaluate this risk on a per element basis, and to "glue" the lens elements laterally. Opto-mechanical designs created by this process are fully compatible with our manufacturing process.

Day/night Lenses

Due to the chromatic aberrations most lenses can only be focused for either visible OR NIR wavelength, not both spectral regions simultaneously.  Using advanced design technique and unique optical materials, we have created a series of day/night lenses that are chromatic corrected for the entire visible-NIR spectral range.  These lenses are in focus for both visible and NIR at the same focus distances.  Sunex Day/Night lenses have enabled our customers to produce more functional cameras for day/night security and surveillance applications. Visit Day/Night products page.

Dewarping Algorithms

Images from super wide-angle and fisheye lenses have significant amount of barrel distortion. Post-processing can "dewarped" these images and make them for useful or pleasant for intended applications.  However, most existing algorithms makes unrealistic assumptions about lens behaviors. Sunex has developed a new set of dewarping algorithms based on the real-world lens behaviors from our extensive experience in lens manufacturing. These algorithms are powerful and flexible enough to allow the adjustment of lens distortion interactively (click here for a demo).

Manufacturing Innovation

Lean assembly process

Precision optics manufacturing require specialized equipments.  Traditional process is to manufacture in batch mode. This can cause issues in terms of batch-to-batch quality variations, long-lead time to respond to customer needs, and increased cost and inefficiency in the supply chain.  Sunex has developed and perfected a unique optical manufacturing process based on the concept of "lean" manufacturing.  Using "one-piece" flow manufacturing cells, we are producing multi-element lens assemblies with higher level of quality and reduced setup time. This will provides significant waste reduction and cost saving to our customers.

High temperature plastic material

Aspheric lens elements made from injection molded plastic are cost-effective for high volume applications. However, traditional plastic material and coatings are limited to room temperature applications.  At elevated temperature the coating may degrade, and the substrate plastic material will also soften. In collaboration with our partners, we have developed unique material and process technologies that overcome this problem.  We successfully commercialized this technology for high volume automotive lenses.

Testing Innovation

Wide angle optics

Functional testing of super wide-angle and fisheye lenses can be challenging given the high field angle in the object space.  Sunex has developed proprietary optical testers suitable for testing such lenses in volume production. This method is used as part of our "lean" assembly process to enable the quality of the finished products.

Reliability testing

We have built an in-house product reliability testing lab with the following capabilities:

• Temperature and humidity
• Shock and vibration
• Salt fog/spray
• Air, dust and water ingress
• Chemical resistance
• Surface durability