Cone cell

When illuminated from the side, rod lenses can be used for the same applications as plano-convex cylinder lenses. Previous examples include line generation, astigmatic collimation, and anamorphic beam shaping. Rod lenses are especially effective as line generators because the double-convex shape has more optical power than a plano-convex shape of the same curvature. Rod lenses, therefore, have very short focal lengths, which results in a larger fan angle.

Total internal reflection of a laser beam in a block of acrylicA rod lens that is polished on both of its edges can be used to transport light along the length of the rod, from one face to the other. The light stays confined within the rod because of a phenomenon called total internal reflection (TIR), which, in effect, makes the exterior of the rod act as an almost perfect mirror. Rods used in this manner are frequently called "light pipes" and are often used for illumination systems.

Rodlens manufacturer

The rod lens is a cylindrical lens with a cylindrical geometry and a polished shell, while the two flat end faces can be ground. It is similar to a ball lens used to focus in two directions. They can be used as cylindrical lenses for beam collimation, focusing and imaging.

Cylindrical lens

Working in the near-IR can result in greatly improved contrast depending on the characteristics of the item under inspection. Information captured in near-IR images can be significantly different than those images captured with white light based on the absorption and reflection properties of the items being inspected. It’s usually impossible to tell how an image will appear in the near-IR without experimenting. Most digital cameras have excellent near-IR sensitivity, and these tests can be performed quickly and easily by placing a visible blocking/IR pass filter over the camera lens in conjunction with a broad spectrum light source or sunlight.

It is also possible to grind and polish the end of a rod lens, creating a long circular lens with a very narrow diameter. Such lenses are ideal for rigid endoscopes, a type of medical instrument used by surgeons to view regions inside the body. Conventional microlenses are not ideal for endoscopes because they are challenging to align along the length of the tube. Using rod lenses eliminates this problem because such lenses self-align to the tube diameter. Additionally, rod lenses provide structural support within the endoscope tube. Utilizing rod lenses in this way requires precise matching of the surface curvatures, the lengths of the rods, and the spacing between the rods. It is interesting to note that the inventor of the rod-lens endoscope, the brilliant optical scientist Harold Hopkins (who also invented the zoom lens), solved this difficult optical design challenge using a desktop calculator.

Conventional charge-coupled device (CCD) and complimentary metal oxide semiconductor (CMOS) sensors can exhibit near-infrared (IR) sensitivity from 700 nm to approximately 1,100 nm and can be converted to an inexpensive infrared (IR) imager with the use of a near-IR bandpass filter.

Rod lenses are available with different optical materials, mostly with glasses like fused silica and BK7, but also with crystalline materials like YAG or silicon, e.g. for infrared optics. Rod lenses can have diameters of a few millimeters, but there are also cylindrical microlenses with substantially smaller diameters. Small-diameter rod lenses are frequently used as fast-axis collimators for diode bars.

RodLens endoscope

A rod lens is a cylindrical lens which has the geometrical form of a cylinder and has a polished mantle, while the two flat end surfaces may be ground. It is analogous to a ball lens for focusing in both directions. They can be sued as cylindrical rod lenses for beam collimation, focusing and imaging.

VY Optoelectronics Co.,Ltd. has always been based on the concept of "Integrity and Innovation,Quality-oriented".Continuously providing customers with high quality Optical lenses & Laser Optics and perfect service. We sincerely welcome customers in domestic and abroad to establish cooperation with us to develop together and create a better future in the field of optics!

MidOpt IR bandpass filters are matched to the output wavelength of infrared light-emitting diode (LED) and laser diode (LD) illumination. In the presence of normal daylight conditions, the desired contrasting effect is often lost without the use of visible blocking near-IR pass filters.