Early Projector

This Roman artifact is considered a possible precursor to the magic lantern. According to the Italian engineer and author Flavio Russo, placing the flame of a candle or small lantern behind the elliptical lens could project the image or portrait painted on its surface onto a white wall, operating on the same basic principle as modern slide projectors. A comparable concept was later explored in the 17th century by Athanasius Kircher, who demonstrated the projection of images using light and lenses—an early step toward the development of the magic lantern.

elliptic lens with portrait
Portrait on an elliptic lens, artifact from Pompei – Naples National Archaeology Museum.

Bamboozle your mind with illusions

Bamboozle your mind with Super Optical Illusions – my book of brain boggling artworks is a clever gift for curious-minded children. Find hearts that beat in the middle of the page and snail shells that spiral off into infinity. Enjoy a preview of my eye popping illustrations below and look for many more in Super Optical Illusions – available now!

As an author, designer, and researcher in the field of visual perception and creative thinking, I like to combine art, psychology, cognitive sciences, and recreational logic to test people’s ingenuity.

I have created or adapted most of the illusions contained in my books. Many were created and perfected during my workshops which are held for the benefit of children and adults alike (more information at: http://www.archimedes-lab.org/prospatelier.html).

Try to solve the optical illusion puzzles below without looking at the answers.

The Football

The Football

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Super Optical Illusions

The outside world is mediated through our sense organs, so what we perceive and feel are just representations of reality. The only things we cannot doubt are our inner emotions: we cannot doubt that we are happy, sad, in love, or in grief, when such states apply. The only other thing we cannot doubt is… to doubt!

Super Optical Illusions (aka Xtreme Illusions 2) is a children book project I enjoyed to make three years ago for the publishers “Carlton Books” [amazon.co.uk], “National Geographic Kids” [amazon.com] and “Ça m’intéresse” [amazon.fr]. It looks really fantastic and my pictures are large to enjoy the details! It is a family book that will encourage the young reader to explore the mysteries that lie right inside our own minds (including the key scientific concepts of perspective and perception).

Super Optical Illusion

Book Cover

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Reuleaux-triangle intermittent mechanisms

The Reuleaux triangle is a curious geometric shape: it looks like a rounded triangle, yet it has a remarkable property. Each side is an arc drawn from the opposite vertex, and together these arcs form a curve of constant width. In other words, no matter how you measure it—between two parallel lines—the width always remains the same.

Because of this property, a curve of constant width can act as a rotor inside a square. As it turns, the shape remains in contact with all four sides of the square at every moment, tracing a continuous motion while never leaving the boundary.

Mechanisms based on intermittent motion appeared early in mechanical engineering. One of their first practical uses was in sewing machines, where motion had to advance in precise steps rather than continuously. Today similar mechanisms are widely used in devices that move film frame by frame—such as cameras, projectors, and film-processing equipment—where controlled, stop-and-go motion is essential.

Reuleaux mechanism
Reuleaux mechanism 2

What color does it look to you?

1 in 12 people have some sort of color blindness that makes them unable to distinguish certain colors or shades of colors from others. Color blindness is, however, an inaccurate term to describe a lack of perceptual sensitivity to certain colors; a more precise term is: Color Vision Deficiency (CVD). Color blindness is the most commonly used term though it is misleading if taken literally, because colorblind people CAN see colors, albeit they cannot make out the difference between some couples of complementary colors. Color vision deficiency is not related to visual acuity at all and is most commonly due to an inherited condition. Red/Green color vision deficiency is by far the most common form, about 99%, and causes problems in distinguishing reds and greens. There is no treatment for color vision deficiency, nor is it usually the cause of any significant disability.

The most commonly used test to detect color vision deficiencies is the Ishihara Color Test.

Color vision deficient people have a tendency to better night vision and, in some situations, they can perceive variations in luminosity that color-sighted people could not. In fact, most color blind people can easily read what is written in the dotted pattern below… If you fail the test, that means you probably have the full range of color sensitivity that is attributed to color-sighted people.
[Highlight the blank space to see the answer: NO]

Reverse Ishihara Color Test

The visual art of concealing

In my book “Hidden Picture Puzzles“, I treat of hidden things in plain sight.

Steganography” is the art and science of hiding a secret message within a larger one, in such a way that no one suspects its presence. The old Swiss banknotes offer some interesting examples of steganography. In the picture below you can see the back of a Swiss ten-franc bill. The small part surrounded by the blue square contains a microtext, if we strongly enlarge it we may read a short bio of the Swiss architect Le Corbusier both in German and in Romansch:

Le Corbusier hat als Architekt Urbanist maler und Theoretiker Bahnbrechende und Visionäre Anwendungen für den Wohn- und Städtebau verwirklicht…

Swiss bill

A Window on the World

The human being is a sponge who absorbs the changes of the physical world surrounding him. Actually, if the physical world had been unchanging, we wouldn’t need to receive sensations on the world that surrounds us since all would be static and everything would definitely have its final place!

Our sense organs continuously check, then, the changes of our immediate environment to allow us to act and react in keeping with it. If we see a wall in front of us, for example, we won’t charge into it, of course, but try to avoid it! Our senses however detect only a part of the reality – the most useful for us – and translate it in an ‘analogical’ way. Yes, our senses work analogically… For instance, it’s difficult to consider a single color in a distinct way, but always in relation to others. The same red color will be perceived differently according to the content or the context where it lies within.

Every living being has a ‘repertoire’ of sense organs which is peculiar to him, with a particular predilection for one or two sense organs: the human being favors sight; the dog, smell; for bats, it’s hearing… Concerning the color’s perception, animals do not all see in the same way because they aren’t perceptive to the same part of the luminous spectrum. Here are two extreme cases: insects, for example, see the ultraviolet rays, while on the other hand, some snakes can perceive infrared rays.

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