The most classic of the standard lenses is the conical lens. A large part of these lenses rely on total internal reflection and are called TIR (Total Internal Reflection) lenses. Usually the TIR lens is an axisymmetric design that provides a beautiful circular spot that can be combined into multiple LEDs to form an array lens or a single holder for easy installation and light control.
TIR lens VS reflector
In fact, the basic working principle of the two is the same, but the TIR lens has more control than the TIR lens, because each light of the TIR lens is controlled and utilized, and a large part of the light of the reflector is not in contact with the reflection. The surface is uncontrolled, and it is easy to see in the small-angle optics that the light pattern of the reflector is as sharp as that of the TIR lens (in short, the side spot of the reflector is larger).
Type of lens:
Figure: From left to right: 1. True concentrating (-RS), 2. Soft concentrating (-SS), 3. Diffusion concentrating (-D), 4. Medium angle (-M/-M2), 5 , ellipse angle (-O), 6, large angle (-W/-WW/-
Different optical properties use different TIR lenses, and the size of the lens and the LEDs directly affect the optical performance. Therefore, the angle, the light intensity and the efficiency are inaccurate without first mentioning the condition. A good optical design must be followed. The perfect combination of the light distribution of the LEDs can achieve good optical results. There is no versatile product in professional optical design, and some are targeted to optics and targeted applications.
Let's take a look at each of the different optics in the TIR lens family:
True condenser lens (-RS)
In the lens family, such lenses are the most concentrated, in order to achieve high cd / lm (peak light intensity) but also lead to missing part of the light mixing performance, such lenses are easy to identify, generally the surface is crystal clear Partially, it may be hollow. Application of this type of lens in the main direction comprising: light projecting lamps, spotlights, wall washer remote like. Cases such as bridge lighting, high-rise building lighting, indoor spotlights, etc.
Soft condenser lens - SS
From the comparison between the following figure and the previous one, the biggest difference between this type of lens and the concentrating lens is that the surface is treated with soft light, so that a better light quality distribution can be obtained, but compared with the previous concentrating lens. Cd/lm will be relatively low and the angle will be slightly wider. The application of optics here is also mainly light projection, spotlights and the like. No one is good or bad, both are to meet different light application needs. Fish and bear's paw are good things, but the application direction is different.
Diffusion condenser lens (-D- )
Please look at the figure below. This type of lens with diffused surface design has the smoothest light distribution among the three condenser lenses. In contrast, the peak intensity of cd/lm is slightly larger than that of the lens with soft surface design. A little lower, but the angle between the two is similar. Because its surface is diffused surface treatment, the light mixing effect will be better, and the glare control effect will be better. Therefore, the application of the wall washer and the mid-range spotlight and spotlight effect are all levers.
Medium angle lens (-M/M2)
The light distribution effect of this kind of lens is between the condenser lens and the large-angle lens. The surface has a small "pincushion" surface design. If an LED is placed inside, it looks a bit like a "flying insect's eye". Generally speaking, there will be no rough diffuse surface. It is widely used and can be used in a wide variety of luminaires with uniform light distribution.
Elliptical light lens (-O/ -O-90)
This type of lens is the most widely used in building wall washers and advertising light box lighting. The light distribution of an ellipse is such that one axial light distribution is very wide and the other axial direction is a small light angle. The purpose is very simple, the light type represents everything, the width is wide and uniform for the C0-C180° light distribution, and the narrow axial C90-C270° light distribution is to spread the light farther. This type of lens also has a version with its own deflection angle, which is convenient for wall-washing applications where the lamp cannot be adjusted.
Large angle lens (-W-W4)
This category belongs to the large-angle category in the TIR family lens, which is subdivided into multiple angles from 40° to 80°. The larger the angle, the wider the light distribution. The standards for these types of lenses generally have rougher diffuse surfaces, but some lenses have a medium "pincushion" surface or curved surface, or both. The application of such lenses is also very broad and the like.
