Overview of Lenticular printing

Every day, there are hundreds perhaps even thousands of advertising messages that are knocking on your head and trying to gain access to the part of your brain that decides to buy things. With so much money at stake, it's very surprising that to catch our attention advertisers go to such extraordinary lengths.

So to stay one step ahead the advertisers have to keep thinking of new tricks. Book covers, printing posters, large 3D photo, magazines with lenticular images that seem to change as you move your head is some of their latest ideas.

Making of a lenticular

Lenticels on a book cover

Photo: On a book cover you can see the individual lenticels. Magnifying one of the sliced images underneath it. Different lenticulars have different pitches, which indicated the number of lenticels per inch (LPI). At different distances from the viewer, they work differently. In making a convincing lenticular print both these factors the pitch and the viewing distance needs to be taken into account from a large 3d photo manufacturer.

You need to take your two different images and load them into a computer graphics program. In dozens of thin strips, the program cuts each image and then weaves them together so that the strips from the first image alternate with the strips from the second. This process is referred to as interlacing.

It becomes a confusing mess if you look at the doubled-up image printed this way, but it is not for long. Next, on top of the doubled-up image, you place a transparent plastic layer. This is made of dozens of separate thin, large lenticular poster China hemispherical lenses called lenticels. These refract (bend) the light passing through them as a result no matter whichever side you're looking from, you see only half the printed strips. The image flips back and forth too like a kind of visual see-saw when you move your head back and forth.