Difference between revisions of "Cree"

[[File:Ansi-white.jpg|thumb|Chromaticity chart with tint bins used by Cree]]Cree is a [[LED]] manufacturing company based in Durham, North Carolina. They produce a number of different models of high output LED's that are widely used in flashlights. They do not actually make flashlights, though some companies will describe their product as a "Cree flashlight." This refers to the LED inside the flashlight.  

Cree classifies tints of white LED's as being warm, neutral, and cool, but has recently added "outdoor white" in between and overlapping neutral and cool (4000-5300K). Tints are binned using a system based on the [[ANSI White]] standard. Cree's tints subdivide and expand on the ANSI regions giving bins such as cool 1B, neutral 5B1, and warm 7D2, though many other tints and subdivisions are available. Click on the graphic at right to see all of the bins, though not all bins are available.

In addition, Cree produces High [[Terminology#CRI|CRI]] LED's, with CRI values of 80, 85, and 90 represented by bins H1, P1, and U1 respectively (separately, L1 represents normal CRI white LED's, and O1 is outdoor white).

Large die high power LED has versions that run at 6, 9, or 36 volts with maximum power of 18 watts, first available around November 2012. The LED is 8.9mm x 8.9mm and the light will be floody compared to the smaller XM-L. The first production lights to use this LED were the Crelant 7G10 and Solarforce S200, introduced in May 2013. The LED is binned at 85°C. The bins shown below have been increased by 15% to give output at 25°C for easier comparison to other LED's.

[[File:Creexb-d.jpg|thumb|Cree XB-D is similar to the XT-E but smaller.]]Very compact LED (the die is mounted on a chip 2.45 mm square opposed to 3.45 mm square for XP series) introduced in February 2012, promising lower cost. Should provide similar brightness to XP-E LED's. First available units were warm white with Q2 brightness bin (at 350mA). This LED is used in some budget Ozark Trail 3xAAA lights at Walmart. The XB-D is binned at an operating temperature of 85° C instead of 25°, so in order to directly compare its output to other LED's that are typically binned at 25 degrees, the output numbers in the table below have been increased by 14% from what is shown in the datasheet (see [[XB-D output]] for the 85° numbers). Can be driven up to 1000mA. [http://www.cree.com/products/pdf/XLampXB-D.pdf Datasheet], [http://www.cree.com/news-and-events/cree-news/press-releases/2012/january/120111-xbd press release].

[[File:Cree-xml.jpg|thumb|Cree XM-L LED with 6 yellow strips and 3 brass bonding wires]]Widely used in high power flashlights, this larger die LED was first available in November 2011, offering efficacy of 160 lumens per watt at 350mA. Output is as high as 340 lumens at 700mA (bin U3, which is still rare) therefore it is more efficient and puts out more light at any current than earlier single-die Cree LED's. However the biggest improvement to overall output is the XM-L can be driven to 3000mA for 1100 lumens of output. Because the XM-L is binned at 700mA, the bin numbers do not correlate exactly to those of the smaller die LED's which are binned at 350mA. The LED die is 2mm x 2mm on a 5mm x 5mm substrate with 6 yellow strips and 3 bonding wires as opposed to the XP-G with 4 strips and 2 bonding wires and the XP-E with 3 strips and 2 bonding wires. The first production lights to feature the XM-L were versions of the [[ThruNite]] Catapult V2 (first to ship), [[EagleTac]] M3C4, a [[4Sevens]] Quark MiNi, and the [[JETBeam]] M1xm, introduced in December 2010, but budget retailer KaiDomain had LED's and [[P60]] drop-ins as well as P60 lights around the same time. Neutral and warm tints began shipping in March 2011. [http://www.cree.com/news-and-events/cree-news/press-releases/2010/november/101110-xml Press release] [http://www.cree.com/products/pdf/XLampXM-L.pdf Cree XM-L datasheet]

Same 5mm x 5mm size as the original XM-L but with up to 20% more output. Introduced in December 2012. Like the XP-G2, the XM-L2 is silver on top, has two bonding wires, and the die has dots instead of lines. The XM-L2 is significantly larger than the XP-G2 and has a round hole at the upper left as opposed to the XP-G2's square hole. The LED's are binned at 85°C, so the values shown below have been increased by 13.7% to make comparisons with other LED's binned at 25°C easier. The first production lights to feature the XM-L2 were the [[ThruNite]] Catapult V3 and TN31 in January 2013, followed by a number of Xeno lights which also had options for neutral tints in Feburary. [http://www.cree.com/news-and-events/cree-news/press-releases/2012/december/xml2-intro Press release].

[[File:Cree-xte.jpg|thumb|Cree XT-E LED]]Introduced in February 2012, the XT-E has the same size chip as the XP series but seems to have a wider viewing angle for more flood and less throw. Can be driven up to 1.5A and available in bins up to R5 (at 350mA). This LED is binned at an operating temperature of 85° C instead of 25°, so in order to directly compare its output to other LED's that are typically binned at 25 degrees, the numbers in the table below have been increased by 14% (see [[XT-E output]] for the 85° numbers). Cree introduced the XT-E as a low-cost, high efficiency LED capable of 148 lumens per watt at 350mA, offering higher lumens per dollar. The LED is not a flat square, but has an X shaped hill on the surface. The beam is like a small XM-L with a large hotspot and some varying tint across the beam. [[EagleTac]] announced that the XT-E would be an option in its D25 clicky series in April 2012, but XT-E lights were never actually released, supposedly due to beam quality issues. At about the same time, KaiDomain offered P60 drop-ins and flashlights with the XT-E. Cree uses the XT-E LED in its line of household light bulbs, introduced in 2013. [http://www.cree.com/products/pdf/XLampXT-E.pdf Datasheet], [http://www.cree.com/news-and-events/cree-news/press-releases/2012/february/120207-xte press release].