Propeller Clock using Arduino Nano Micro-controller

Once John Lubbock rightfully propounded, “What we see depends mainly on what we look for”. Perfection is a just a illusion whereas Perception is the real vision. This “illusion” is based on inertia of human eye. Propeller clock is a special kind of circular LED display. It is making use of POV, a scientific phenomena termed as ‘Persistence of Vision’, which means that if something appears in the same spot consistently, at least 50-60 times per second, our brains think that it’s permanently there when it is not. The term ‘Persistence of Vision display’ or ‘POV display’ has been used for LED display devices that compose images by displaying one spatial portion at a time in rapid succession (for example, one column of pixels every few milliseconds). A two-dimensional POV display is often accomplished by means of rapidly moving a single row of LEDs along a linear or circular path. The effect is that the image is perceived as a whole by the viewer as long as the entire path is completed during the visual persistence time of the human eye. A further effect is often to give the illusion of the image floating in mid-air. This implementation will be a coordination of electrical, electronics and mechanical engineering. Keywords: Persistence of Vision, Arduino Nano, Micro-controller, Led’s, Propeller, POV

How Do We See a Changing World?

This chapter begins an analysis of how we see changing visual images and scenes. It explains why moving objects do not create unduly persistent trails, or streaks, of persistent visual images that could interfere with our ability to see what is there after they pass by. It does so by showing how the circuits already described for static visual form perception automatically reset themselves in response to changing visual cues, and thereby prevent undue persistence, when they are augmented with habituative transmitter gates, or MTM traces. The MTM traces gate specific connections among the hypercomplex cells that control completion of static boundaries. These MTM-gated circuits embody gated dipoles whose rebound properties autonomically reset boundaries at appropriate times in response to changing visual inputs. A tradeoff between boundary resonance and reset is clarified by this analysis. This kind of resonance and reset cycle shares many properties with the resonance and reset cycle that controls the learning of recognition categories in Adaptive Resonance Theory. The MTM-gated circuits quantitatively explain the main properties of visual persistence that do occur, including persistence of real and illusory contours, persistence after offset of oriented adapting stimuli, and persistence due to spatial competition. Psychophysical data about afterimages and residual traces are also explained by the same mechanisms.

Early History of Illusions

Illusions are considered in the context of the history of vision rather than the history of psychology. For much of its long history, the study of vision has been confined to naturalistic observation, and many motion illusions were observed in the natural world. With the move to the laboratory, the oddities of visual perception multiplied, and they received ever more detailed scrutiny. This survey examines the origins of research on visual illusions in both the natural world and the laboratory. It commences with celestial illusions and pictorial representation then proceeds to subjective visual phenomena and spatial illusions like ambiguous figures and geometrical optical illusions. However, most attention is paid to motion illusions; these include visual persistence and stroboscopic motion, induced motion, motion aftereffects, visual vertigo, and autokinetic sensations. The basis for the explosion of research on visual illusions in the nineteenth century is speculated upon.

Two Types of Visual Objects

While it is widely accepted that human vision represents objects, it is less clear which of the various philosophical notions of ‘object’ adequately characterizes visual objects. In this paper, I show that within contemporary cognitive psychology visual objects are characterized in two distinct, incompatible ways. On the one hand, models of visual organization describe visual objects in terms of combinations of features, in accordance with the philosophical bundle theories of objects. However, models of visual persistence apply a notion of visual objects that is more similar to that endorsed in philosophical substratum theories. Here I discuss arguments that might show either that only one of the above notions of visual objects is adequate in the context of human vision, or that the category of visual objects is not uniform and contains entities properly characterized by different philosophical conceptions.