Say one thousand, say ten thousand, what is the light distribution curve of lamps?

　　Lamps are indispensable and important items in people's daily life. Since human beings know how  control flames, they have undersod how  get light in the dark night. From campfires, candles, tungsten filament lamps, incandescent lamps, fluorescent lamps, tungsten halogen lamps, high-pressure sodium lamps  LED lamps, people’s research on lamps has never spped, and the requirements for lamps are increasing, both in appearance and optical parameters. Come higher.

　　A good appearance design can create a pleasing appearance of the lamp, and a good light distribution gives the soul of the core of the lamp.

　　1. What is light distribution?

　　First of all, give a chestnut, how  illuminate a tree?

　　Like this? Seems perfect~

　　However, if the installation distance is limited (for example, there is a pond next  the tree), the entire tree cannot be happily illuminated at a suitable distance.

　　If it is installed on the opposite side of the water, a part of the light will be wasted. If it does not shine on the tree, it shines on the home of the opposite resident, making the resident very uncomfortable and also causing the opposite effect of light pollution.

　　From another angle, if you use optical accessories, change the width of the beam  narrow the light, so that the light can shine on the tree?

　　Similarly, with optical accessories, we can arbitrarily adjust the distance between the light source and the illuminated object, and we can even let the light shine on the tree from the other side, giving the effect of icing on the cake.

　　Oh~ the lamps can be used in this way!

　　Figure: This is the light distribution

　　Light distribution refers  the light distribution of the lamp, such as the direction of the light, the width of the light, and so on.

　　Light distribution of typical light sources:

　　A light bulb-360°, illuminates the entire range of the space, without light distribution.

　　The light of the bulb is evenly distributed in space, there is no primary or secondary, and it does not go where it should go.

　　LED luminous body-120°, evenly distributed in half of the space, almost full range on one side of the space, it can also be called no light distribution.

　　2. Why do lamps need light distribution?

　　What is the role of light distribution? If you want  know why, you can take a look at your home first. Nowadays, the status quo of indoor lighting is that fluorescent tube ceiling lamps are all over the world. Once installed, they can be bright. Is the lamp on? Very bright! Are the spaces uneven? Very even! Does the light source festival not save energy? Very energy saving!

　　But why is it still dark on the deskp?

　　How  solve? Join the lighting design!

　　Distribute light reasonably according  space use and behavior, and let light go  where it is needed.

　　For example, when dining, time needs  be on the table, and when watching TV, light needs  appear in the background  provide a good and comfortable look and feel.

　　Add lighting design  distribute the light in a targeted manner rather than uniformly distributed throughout the space. This is the role of light distribution.

　　3. No light distribution vs. light distribution

　　Round one:

　　Picture: Without light distribution (left) with light distribution (right)

　　No light distribution: the light diverges everywhere, and a lot of it is wasted  unnecessary places (as shown on the left)

　　There is light distribution: light controllable, free  control, precise light control, which means  hit which one (pictured on the right)

　　Round two:

　　Picture: Without light distribution (left) with light distribution (right)

　　No light distribution: severe glare, dazzling, uncomfortable light (pictured on the left)

　　With light distribution: comfortable light, reduce glare, comfortable and healthy light environment (as shown in the right picture)

　　Round three:

　　Figure: No light distribution: simple lighting application.

　　Picture: With light distribution: Provide a rich and diverse light environment for life.

　　There is no difference in light distribution, I don't need  say more about it.

　　4. How  describe the distribution of light?

　　Light distribution is  control the light distribution of lamps, so how  describe the light distribution in a common language?

　　1. The most simple and intuitive method of description-the schematic method

　　As shown in the figure below, blue represents light and orange represents light. It's intuitive, but it's just a stereotyped description, without quantification, and it can't express brightness. This type of method can only describe an approximate direction and range of the light distribution, and can only be used as a schematic diagram for reference.

　　2. The simplest method of digital and accurate description-beam angle

　　Beam angle: Reflected on the illuminated surface, it is the size and brightness of the light spot.

　　For the lamp cup of the same power, the larger the beam angle, the smaller the central light intensity, and the softer the spot.

　　On the contrary, the smaller the beam angle, the greater the central light intensity, and the stronger the light spot.

　　Figure: Different beam angles have different light distribution effects

　　The application of different beam angles: the lower left picture only illuminates the tea set, while the lower right picture also illuminates the table.

　　Different beam angles have different effects on the back shadow formed by the illuminated surface. The narrow beam angle has a better three-dimensional effect.

　　In actual application, it is necessary  comprehensively consider parameters such as projection distance, direction, and environmental brightness, and choose different beam angles according  needs.

　　Figure: Using different beam angles  form different space atmospheres. The first picture is evenly illuminated, and the atmosphere and corners are not so strong. Light beams with different beam angles shine on the same work  get a different feeling.

　　Picture: Sculptures do not necessarily need  use narrow beams  show the three-dimensional effect. You can use a narrow beam  highlight details (as shown in the right picture), or you can use a wide beam  evenly highlight the outline (as shown in the left picture), depending on the artist's creative ideas. Choose the appropriate beam angle according  the atmosphere required  display the artwork.

　　But can a number describe the distribution of light? Sometimes the same beam angle, the effect is quite different.

　　for example:

　　The two light spots in the figure below are both 30°, and the left side is obviously softer. The difference between the two cannot be described by the beam angle.

　　give another example:

　　The two 100° light sources in the picture below show that the two walls are brighter on the left, the middle is darker, and the wall and the ground on the right are bright. How do you describe the difference?

　　This leads  a question: how  describe the light distribution of a special shape?

　　The above only lists the special cases of the light source shape. In addition, the beam angle cannot describe the intensity of light. Therefore, the distribution of light cannot be described with a simple number.

　　3. Accurately describe the light distribution of lamps-light distribution curve

　　The light distribution curve is very intuitive, the narrow beam is like a sharp knife, a very thin one, while the curve of the wide beam is fat:

　　Figure: The light distribution curves of lamps with different beam angles of 3°, 6°, 16°, 30°, and 50°.

　　Another example is the two 30° light sources with different effects mentioned above. If the light distribution curve is used  describe the 30° curve on the left, the tip of the curve protrudes outward, and the curve on the right is retracted in an M shape.

　　Similarly, for the two lamps with a beam angle of 100° mentioned above, the light on the left is the strongest  the side, while the light on the right is evenly distributed and round.

　　The light distribution curve can not only clearly describe the distribution and intensity of light, but also describe the special light distribution well: