In physics and color science, the Planckian locus or black body locus is the path or locus that the color of an incandescent black body would take in a particular chromaticity space as the blackbody temperature changes. It goes from deep red at low temperatures through orange, yellowish white, white, and finally bluish white at very high temperatures.
A color space is a three-dimensional space; that is, a color is specified by a set of three numbers (the CIE coordinates X, Y, and Z, for example, or other values such as hue, colorfulness, and luminance) which specify the color and brightness of a particular homogeneous visual stimulus. A chromaticity is a color projected into a two-dimensional space that ignores brightness. For example, the standard CIE XYZ color space projects directly to the corresponding chromaticity space specified by the two chromaticity coordinates known as x and y, making the familiar chromaticity diagram shown in the figure. The Planckian locus, the path that the color of a black body takes as the blackbody temperature changes, is often shown in this standard chromaticity space.
LED Wiki: Wi-Fi, Zigbee and Bluetooth compared
Key characteristics of ZigBee, Wi-Fi and Bluetooth
|Range||10-100 meters||50-100 meters||10 – 100 meters|
|Networking Topology||Ad-hoc, peer to peer, star, or mesh||Point to hub||Ad-hoc, very small networks|
|Operating Frequency||868 MHz (Europe) 900-928 MHz (NA), 2.4 GHz (worldwide)||2.4 and 5 GHz||2.4 GHz|
|Complexity (Device and application impact)||Low||High||High|
|Power Consumption (Battery option and life)||Very low (low power is a design goal)||High||Medium|
|Security||128 AES plus application layer security|| ||64 and 128 bit encryption|
|Typical Applications||Industrial control and monitoring, sensor networks, building automation, home control and automation, toys, games||Wireless LAN connectivity, broadband Internet access||Wireless connectivity between devices such as phones, PDA, laptops, headsets|
— Wi-Fi, Zigbee and Bluetooth comp...