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Nov,2015 E-newsletter

CLEAR Lighting at the Hong Kong International Lighting Fair (Autumn Edition) 27–30 October 2015 Organized by The HKTDC and held at the HKCEC , the Hong Kong International Lighting Fair (Autumn Edition) is the largest autumn lighting fair in Asia, which has attracted a large number of exhibitors across the globe. CLEAR’s booth was located in 5E-J34. There was a "A" poster, which gave a simple introduction of CLEAR. At the other places, different applications of the flex neon light were displayed as well. Especially the application of the injection molding connectors, it makes the connection of the lights more tightly. For some application, it can even achieve seamless connection visually. At the same time, we have also displayed some brand new products, such as Nichia CCT Dynamic White CLEAR’s booth 5E-J34 has attracted a lot of new and old customers, because of the high quality of product. Thank you very much for your visits, also many thanks to you for good suggestions and requirements for our products. CLEAR, as a trustable partner, will continue to improve our products and innovate in them.

Welcome to visit our booth: 5E-J34

We will participate in HK international Lighting Fair 2015.Welcome to visit our booth at 5E-J34.

Aug,2015 Newsletter

There are 3 sections: 1. Purple LED to Replace Blue LED? (Quote from http://www.ledinside.com/news/2015/8/purple_leds_to_replace_blue_leds) 2. CLEAR Summer Holiday in Easter Hawaii

LED Knowledge

1). Luminous Flux (Ô)

The SI unit of luminous flux is the lumen (lm). The luminous flux Ô [lm] indicates all the radiated power emitted by a light source in all directions.

2). Candela

The candela is the SI base unit of luminous intensity; that is, power emitted by a light source in a particular direction
Luminous intensity in different directions is different from a particular light source.

3). Beam angle (unit: ±)

The beam angle is the angle between the two directions opposed to each other over the beam axis for which the luminous intensity is half that of the maximum luminous intensity. Beam angle can tell people how the beam transmits from beam axis.

4).  Lux (lx)

 The lux (symbol: lx) is the SI unit of illuminance and luminous emittance measuring luminous power per area.
1lumen/ ft^2=1foot candlepower 
1lumen/m2=1 lux

5). Correlated Color Temperature (CCT)

The black-body radiator appears of different colors when heated in correlated temperatures. CCT refers to the temperature when the color of the heated black-body radiator corresponds to that of the light source.

6). Color Rendering Index (CRI)

The color rendering index (CRI) (sometimes called color rendition index), is a quantitative measure of the ability of a light source to reproduce the colors of various objects faithfully in comparison with an ideal or natural light source.

7). Luminous Efficacy (lumen/watt)

Luminous efficacy is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power.
[ Luminous efficacy = lumen/watt ]

8).  Lumen Maintenance

Lumen maintenance is the luminous flux output remaining output (typically expressed as a percentage of the maximum output) at any selected elapsed operating time. Lumen maintenance is the converse of lumen depreciation.

9). SDCM & MacAdam Ellipses

SDCM is an acronym which stands for Standard Deviation Colour Matching. SDCM has the same meaning as a “MacAdam ellipse”. A 1-step MacAdam ellipse defines a zone in the CIE 1931 2 deg (xy) color space within which the human eye cannot discern color difference. Most LEDs are binned at the 4-7 step level, in other words you certainly can see colour differences in LEDs that are ostensibly the same color.

These are the three sizes that you'll often see used in the color specifications for light sources. In particular, the 7-step is the standard for color consistency in CFL lamps and in ANSI/NEMA/ANSLG C78.377-2008 American National Standard for Specifications for the Chromaticity of Solid State Lighting (SSL) Products (which is a standard for white light, not colored). 7-step ellipse centered on 3200 K covers a very broad area and spans a 500 K range of color temperatures from 2950 K to 3450 K. The 4-step and 2-step ellipses are tighter standards, which are standards that many light source manufacturers are already working to. The 4-step ellipse is also the standard to which many entertainment industry HID lamps, such as MSR and HMI, have been manufactured for many years. 



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