Illusions; shattered or real?: Optical Illusions

Illusions are the triumph of intellectual foolery, a split between perception and cognition which induces a state of temporary confusion. Any one aspect of a visual scene is spatial ambiguous, these is an innate ambiguity in retinal input which relies on spatial processing for us to make sense of the world. Generally one can encode three-dimensional information from two-dimensional situations, a powerful capability in itself, however illusions introduce a heightened degree of difficulty to the process of perception. Inverse Optics result when our perception and our logic struggle to impose order on a situation and an alternating view of the world is ensured.

Optical illusions bear the trade marks of deliberate visual deception - perceptual error i.e. the incorrect coding of visual information. It is an interesting to present some information on this area within the context of this study as it is the improper visual interpretation of a stimuli that leads into a spatial cul de sac and hence the barrier to acquisition of efficient spatial skills. They play a prominent part in our appreciation of the physical world. Sometimes they must be avoided, but often they may be put to work in various arts. Their widespread existence and forcefulness make visual perception the final judge in decoration, in painting, in architecture, in landscaping, theatre and lighting.

Optical illusions are some times called "errors of sense" and some of them are such, but often they are errors of the intellect. The senses may deliver correctly but error may arise from imagination, inexperience, false assumptions, in correct associations and the recency, frequency, and vividness of past experience. The direct data delivered by the visual sense are light, intensity, color, direction.

Next is the distinction of outline-form and surface-contents. The perception of these by the eyes is so direct and so certain that it may be considered to be immediate. A ring of points is apparently very simple and it might be considered a direct sense perception, but it consists of a number of elemental directions. The perception of solid-form is far more complex than outline-form and therefore more liable to error. It is judged partially by binocular vision or perspective and partly by the distribution of light and shade. Colors may help to mold form and even to give depth to flat surfaces. For example, it is well known that some colors are "advancing" and others are "retiring."

Perhaps of still greater complexity are the judgments of size and of distance. Many comparisons enter such judgments. The unconscious acts of the muscles of the eye and various external conditions such as the clearness of the atmosphere play prominent parts in influencing judgment. Upon these are superposed the numerous psycho-physiological phenomena of color, irradiation, e.t.c.

In vision, judgments are quickly made and the process apparently is largely outside of consciousness. Higher and more complex visual judgments pass into still higher and more complex intellectual judgments. All these may appear to be primary, immediate, innate, or instinctive and thus certain, but the study of the psychology of vision has shown that these visual judgments may be analysed into simpler elements. Therefore, they are liable to error.

In a broad sense, any visual perception that does not harmonize with physical measurements may be termed an "optical illusion." Therefore, this term could include physical optical illusions obtained by means of lenses, mirrors and prisms and also optical illusions such as the mirage. It could also include the physiological illusions of light and color such as after images, irradiation, and contrast, and the psycho physiological illusions of space and the character of objects.

In a more common sense, attention is usually restricted to the last group; that is, to the psycho-physiological illusions that include the perception of space with reference to the character of objects and sometimes motion is also considered.

Many examples of optical illusions may be found around us. Alot of artists have worked with this concept to create scenarios that deceive the eyes and thus create thought provoking, interesting compositions and structures. It is the main area of interest in terms of artistic practice for some graphic artists like M.C. Escher who played around with quirks of perception and perspective to create intriguing images.

Ascending and Descending by MC Escher - 1960, Lithograph

Belvedere by MC Escher - 1958, Lithograph

Swans by MC Escher - 1956, Woodengraving

Print Gallery by MC Escher - 1956, Lithograph

Three Worlds by MC Escher - 1955, Lithograph

The works of MC Escher take the art of optical illusion to an aesthetically precise level. Through clever and intricate geometrical formation and interpretation of the principals of mirroring, shade and shadow his works transport the viewer into a somewhat deluded perception.

Another artist with a similar artistic style is Oscar Reutersvard. Reutersvard is known as the ' Father of Impossible Figures' as he fathered the art of impossible objects i.e. objects which appear to be solid in an image but are impossible to construct in reality. He is often compared to Escher however, there is a distinct difference in the styles of both as Escher used to create inhabited worlds around impossible objects whereas Oscar Reutersvard created pure geometric forms.