Photopic
Vision: |
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Photopic
Vision: Is the
term for human colour vision under normal lighting conditions
during the day. In the range above 3.4 cd/m2, the human eye
uses three types of cones to sense light in three respective
bands of colour. The pigments of the cones have maximum absorption
values at wavelengths of about 445 nm (blue), 535 nm (green) & 575
nm (red). Their sensitivity ranges overlap to provide continuous
(but not linear) vision throughout the visual spectrum. The
maximum efficacy is 683 lumens/W at a wavelength of 555 nm
(yellow). |
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Mesopic
Vision: |
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Mesopic
Vision Is the
term for a combination between photopic vision and scotopic
vision in low but not quite dark lighting situations. The combination
of the higher total sensitivity of the rods in the eye for
the blue range with the colour perception through the cones
results in a very strong appearance of bluish colours, like
those in flowers, around dawn. |
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Scotopic
Vision: |
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Scotopic
Vision is the
term for human vision "in the
dark", below 0.034 lm/m2. In that range, the human eye
uses rods to sense light. Since the rods have a single absorption
maximum of about 1700 lumens/W at a wavelength of 507 nm,
scotopic vision is colour blind. The sensitivity range of
the rods makes the eye more sensitive to blue light at night,
while red light is almost exclusively perceived through photopic
vision. |
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Light Therapy
Light Therapy and treatment using light is being thoroughly researched
and pursued as a new and rapidly growing area of study and application.
Particularly when seeking to manage circadian rhythm’s, proper
and qualified instruction, which is not available on this web site,
should be taken. Most likely the best light sources, for effect,
peak at and around 460nm, sometimes known as actinic blue.
As much as possible, light "treatment" should
be administered on an individual prescribed basis, we all have
differing needs and bio compatibilities. We certainly don't claim
an "All-in-One” solution
from using sulphur plasma lighting. However, until we work out
how to pipe sunlight to the dark side of Earth, we do our best
to provide information that will be useful and helpful. |
Perhaps we should question the real usefulness
of contemporary measurements in Lumens (photopic brightness), Kelvin
(colour compared with heating Carbon), CRI (Rendering compared
with a Tungsten lamp from the previous millennium) and Lumens per
Watt (efficiency and efficacy are not the same). The relevance
of any measurement is very dependent upon the intended application
and the way the user interprets the meaning or significance of
the measurement or definition.
Much has been written about Continuous Full Spectrum
Lighting (CFSL), sadly, nearly all refers to using Fluorescent
Mercury or Metal Halide or Xeon lamps. Most articles written, even
by experts and professional practitioners, no matter if “For” or “Against” CFSL,
could not be much further from the truth. All too often, they have
never even seen sulphur plasma light, they don’t know what
it is and are quite ignorant of Far Eastern research and practices
taking place during the last decade. |
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Continuous
Spectrum |
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Continuous
Spectrum - A spectrum having no lines or bands,
especially a spectrum of radiation distributed over an
uninterrupted range of wavelengths, like Sunlight. |
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Full
Spectrum |
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Full
Spectrum - "Full-spectrum" is not
a technical term when applied to an electrical light
bulb. |
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Full
Spectrum |
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"Full-spectrum" is
a marketing term implying that the product emulates "natural" light.
Sunlight is considered full spectrum, even though the solar spectral distribution
reaching Earth varies with time of day, latitude, and atmospheric conditions,
the filtered and reflected light from the sky, we call skylight. Natural "real" daylight
is thus a combination of sunlight and skylight. |
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Full
Spectrum |
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"Full-spectrum" is
used by www.plasma-i.com to
define light that covers the entire spectrum from ultraviolet
to low infrared. When seen on an SPD (Spectrum Power Distribution)
chart there are no large or sudden variances, no surges
(spikes) or drops (gaps) in power, the coloured chart must
look really "Full", in all wavelengths, all
colours. |
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To see all the colours, to examine a gemstone
or a prestige car’s paintwork, to see all the fractures,
blemishes or faults, no matter what colour the subject is, to visually
examine anything properly and maximize ability to identify differences
in colour, you need Continuous Full Spectrum Lighting (CFSL). |
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