Types of LED Laser Lenses
The lens is a small plastic piece that focuses the laser light into a tight spot. It can be used to engrave and cut through materials. The lens can also be affixed to an optical fiber to create a laser beam that is smaller and more powerful.
A three-dimensional (3D) digital model was developed using the geometric optical theory. It was then subjected to ray tracking and optimization with LightTools.
1. Fresnel Lens
Fresnel lenses are made from multiple rows of concentric rings of refracting surfaces, which are essentially cross-sections of traditional lenses collapsed into one another. They can be much thinner than a conventional lens with the same optical power, saving space, materials and cost. They are also more flexible than a continuous surface, allowing them to bend and curve with the direction of light, which increases their versatility.
There are several types of Fresnel lenses, each with a slightly different design and purpose. The simpler dioptric form, first proposed by Georges-Louis Leclerc, Comte de Buffon and independently reinvented by Augustin-Jean Fresnel for use in lighthouses, uses ring-shaped segments to focus the light into a single point. A more complex catadioptric form uses outer elements that use total internal reflection as well, which allows the lens to capture more oblique light and increase its intensity.
Among the most common applications for Fresnel lenses are magnifying devices and projection systems, such as movie projectors. These lenses can be used to make a beam of light brighter and more focused, and they can even be adjusted for different focal lengths. This feature makes them a useful tool for filmmakers who often work on location without the benefit of a permanent studio.
The lenses are also used in a variety of applications related to energy efficiency and the environment, including solar power generation and heating. They can help to reduce the dependency on fossil fuels by concentrating the photons of the sun onto a small area, which increases the amount of energy that is produced.
2. Mirror Lens
Mirror lenses are the kind of lens you would find in most laser pointers and laser surface inspection systems. led laser lens These lenses combine curved mirrors (catoptrics) with glass lens elements (dioptrics). Their main advantage is that they are much shorter and lighter than a conventional refractive telephoto lens. They also don’t suffer from the chromatic aberrations that characterize classic lenses.
Mirror lens manufacturers claim that their lenses are good quality and produce high-resolution images. However, many photographers have been disappointed with the results of this lens type. The reason for this is that these lenses are quite slow and vignette toward the corners of the frame. Furthermore, they aren’t very good at delivering a clear and sharp image in low-light conditions.
Nevertheless, the fact remains that this kind of lens is very useful for a variety of situations. For example, you may want to take pictures of birds in a bird zoo where you can approach the animals closely and don’t need to worry about a fast shutter speed. Moreover, the mirror lens is very cheap and you will probably be able to get one on ebay for around PS100. This type of lens is also great for a selfie because you can easily fit it into your phone or tablet camera and it will give you the right angle and focus.
3. Fresnel Lens Combination
A multijunction solar cell requires a large optical lens or prism. This is because it has a high efficiency, which means that the light needs to be concentrated. However, the thicker the lens is, the more it weighs and consumes energy. To solve this problem, a method that uses a chiral square Fresnel zone plate (CSFZP) has been developed. This design allows for a smaller, lighter lens that still has the same functional characteristics of a conventional planoconvex lens. The chirality is imposed on the CSFZP by rotating half period zones and twisting the side lobes of the diffraction pattern.
To determine the optimal main design wavelength of the lens, a flow chart has been developed that considers the combination of the solar direct light spectrum and the solar cell response range. In this way, the optimum design wavelength can be led laser lens determined more precisely. This is important because it will result in a higher efficiency of the solar cell.
The optimum design is also used to optimize the fabrication of the holographic lenses. Using MSLA-based 3D printing, the lenses were fabricated and evaluated. The holographic lenses were transparent, tinted, or composite (tinted and holographic) and exhibited excellent focusing performance, with only 4 mm of deviation from the designed value. This indicates that the MSLA-based manufacturing process is appropriate for fabricating these types of lenses.
4. Plastic Optical Lens
This is a very good lens to use with the common laser diodes on the market. It does an excellent job of correcting the stray light around the spot created by the emitters themselves or by the inner walls of the laser module. The resulting spot is smaller and more precise and has a much higher pass efficiency (up to 90%) than the bare diode.
This plastic lens is made from a very strong plastic polymer called CR-39 or similar. It has a moderate F-number and the grooves are coarse which minimizes scattering losses. It has a round shape which can be an advantage or a disadvantage, depending on the application.
It can be difficult to make a small number of these lenses with precision because of the thermal expansion/contraction of the plastic and slight variations in the mechanical properties of the raw stock. However, modern statistical control techniques are allowing the production of more consistent plastic lenses of this type with lower tolerances.
Another benefit of these newer plastic lenses is that they can be molded with photochromic dyes. This allows for color changing lenses on demand! This could be an important feature for many applications. Knight Optical is able to supply competitive quotes for a wide range of standard and custom plastic optics using single or multi-cavity tooling.
