Lighting design method for light-transmitting materials such as light-transmissive film and acrylic sheet

No matter indoors, outdoors, ceilings, walls... more and more occasions, light-transmissive materials such as light-transmissive films and acrylic sheets are used. How to illuminate these materials?

Let's look at a set of images first:

Figure: Chestnuts with successful application of light-transmissive film and translucent plate material. The lighting effect is uniform and the brightness is suitable.

But are you zao? Most designers are too lazy to experiment because of lack of experience, and often do not handle this problem.

Then, it became the following sample paper. Please look for the problem in each picture yourself:

Figure: Common problems with light-transmitting materials: strips, unevenness, over-exposure...

How to avoid these problems? The manufacturer of the light-transmissive film said that there is something to say, they gave suggestions for such lighting arrangements:

For the arrangement of the number of lamps in the soft film ceiling, it is generally determined according to the depth and width of the lamp tube, generally a lamp of 25-35 cm. The number of lamps to be arranged in the soft film ceiling should be determined according to the customer's requirements for light intensity and ceiling construction conditions.

Probably the following picture: Use T5 fluorescent lamps, arranged at a distance of about 35cm. Then a layer of light-transmissive film is applied.

Is this recommended practice really a "universal formula"?

To figure out this problem, we have to start from the beginning: long long ago, there is a temple on the hill, there is an old monk and a little monk in the temple, the old monk and the little monk said...

To make the lighting of the light-transmissive material, first understand the type of light-transmitting material:

a, transparent

b, translucent

c, basically opaque

d, completely opaque (small monk: Master, is it still light-transparent material? Old monk: adults speak, children don't wipe their mouths!)

Their transmission to light is different:

The a and b types are transparent or translucent materials such as transparent acrylic and light frosted glass. When you look at the light source through it, you can see the obvious "light spot" behind it:

c, d two types of opaque but light-transmissive materials, milky white, such as tension film, milky acrylic sheet. When you look at the light source through it, you can't see the light point of the light source, you can only see the effect of the material being "illuminated":

Now the question is coming: How should we choose and arrange the lamps for these different materials?

We have summarized several lighting methods:

1, after the wall-washing

Figure: Chestnuts after wall-washing

2, front wall-mounted lighting

Picture: Two chestnuts in front of the wall-washing lighting (of course, the following C&U... obviously chooses the wrong light distribution. With a wide beam of light, it will become like this. Everyone takes the ring.)

3, backlight box lighting

Figure: Backlight box lighting. However, the excessive spacing of the lamps causes streaking. Solution 1: Encrypt the lamp, but it will cause the brightness to be too high. Therefore, we suggest solution 2: use a small power LED module densely, that is, to achieve uniform illumination, and not too high brightness.

Of course, we must also consider the problem of lighting maintenance, and the bad lights are also inconsistent. Don't think that the light is on, the design fee is taken away, everything is fine, and the design that does not consider the later use and maintenance is not a good design. For example, the following picture, looking for, which place is broken?

Figure: The design of the luminaire should be fully considered.

If your light-transparent film is detachable, it is much easier to overhaul.

Figure: A single module detachable backlight box for easy access.

The method is clear, but can you do it right?

Let's take two more chestnuts. The picture below shows the light-box backlight illumination method. The lamp is densely covered and the brightness is extremely high...

Figure: In order to achieve a uniform effect, the lamp is going to the top! It is also very hard. However, the brightness is extremely high. Energy consumption? Ha ha.

The following is the internal wall-mounted lighting, which does not need too high brightness, so it is right. Just look at the lighting method, please ignore the wrong light color automatically...

Figure: Internal wall-mounted lighting with uniform effect and low brightness. Please ignore the wrong light color automatically.