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More about the Bates Method

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Peter Mansfield in his book “The Bates Method” (1998) introduced Dr Bates this way. The primary tool of Dr. Bates research was the retinoscope, an instrument of elegant simplicity, which allows direct assessment of refraction of the eye. The instrument was coming into regular clinical use while Bates was a student. He was intrigued by the possibilities of this new tool and made it his specialty. Bates was particularly interested in observing animals, children and adults, in normal activity in daylight, as opposed to the artifi- cial surroundings of the consulting room. As his observations continued he began to suspect, then became certain, that the eyes of people seeing normally behaved differently from those who saw abnormally. Further more, whether the vision was on the whole normal or not, the refraction of the eye was constantly changing. Bates then realised that the changes reflected, among other things, the state of mind of the subjects, so the vision would always be nearer to …

More about fluorescent lights

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Fluorescent light tubes was introduced by General Electric at both the New York and San Francisco World Fairs in 1932.
Compact Fluorescent Light CFL was also developed by General Electric in 1973, but the 25 million dollars needed the build a factory was considered too expensive at the time so it was not produced outside the laboratory. The design was eventually copied by others. In 1995, helical CFLs, were manufactured in China and became commercially available. Since that time, their sales have steadily increased.
In 2005 the EU began phasing out incandescent light bulbs in favour of CFL’s the US followed in 2014. The rationale is energy sawing since the CFL are using less energy than the old-fashioned Edison incandescent lamp. However, the newer solid state Light Emitting Diodes L.E.D. technology is far more energy efficient. L.E.D lights use 80% less energy and has a lifespan approaching 40 years of continuous use and has no mercury.
Naturalness of fluorescent light
Incandescent light…

Light, Color Perception and Temperature

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This is the second in the series of articles on light. In this article, we will be discussing about how our eyes perceive light, as well as, colour temperature. Previously, we discussed that there are three standards that are used to measure daylight. Of the three, the D55 standard is used for measuring light at noon.


Units of Light Measurement Different units are used for measuring light. We will be discussing three of them here. A foot-candle is equal to the light from a candle placed one foot away. A 23-watt bulb produces light equal to that produced by 125 candles. Lumen actually measures the power of light that our eyes perceive. A 23-watt bulb will produce light equivalent to 1,600 lumen. The unit that you should be concerning yourself with is the Lux. It factors in the area that a light source will illuminate. That is why, most public places have their minimum lighting requirement specified in Lux. If all this talk of units has you confused, here is an easier way to understand them: …

What You Need To Know About Color Perception

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Colors make the world around us beautiful, but most importantly, colors are vital as they help us distinguish one thing from another. You can recognize a banana that’s gone bad by its color. It is speculated that we see more shades of green than any other color so that our ancient predecessors could spot a predator in the shrubs. We have a come a long way since then in terms of understanding how we see colors. There are two main coherent theories that explain our ability to see colors. Trichromatic theoryTrichromatic theory is also known as the Young and Helmoltz theory. These two scientists carried out an experiment where they used up to three different light sources of different wavelengths so that the resulting mixture of light is the same color as a test field that composed of a single wavelength light. This showed that different colored lights of their respective wavelengths can interact with each other to produce a resultant wavelength. For example, mixing red and blue would giv…

Importance Of Optimum Lighting

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Light is a medium that contains energy as photons and it is astoundingly powerful when it comes to influencing living organisms. In fact, sun is the universal energy source for our planet and all the energy we use can be traced back to the sun eventually. We already know that light can influence the rate of plant growth, but there’s a lot more to it. The visible light is just a small part of the light spectrum and there are various other lights of varying wavelengths. Also, we see the colors that we do because the object reflects that particular color and absorbs all others. This is why plants are green, because they reflect the green light instead of absorbing it. UV light & Us UV rays are also a part of the light spectrum. Most of it is reflected back by the ozone layer and the remaining UV consists of three bands. UVC is dangerous to us while UVB and UVA are responsible for the synthesis of vitamin D, that nice tan we all love, regulating the release of certain hormones and partic…