How to convert the corresponding coordinate value of LED color temperature?

The true color temperature (CT) is the color of light emitted by the black body when it is subjected to this temperature (k). One color temperature is for a set of color coordinates. For example, a color temperature of 6250K, the color coordinates x= y= .

Temperature, from low to high, each color temperature point forms a (curved) line, which is called the "black body color temperature trajectory".

However, what is often referred to as color temperature is actually "correlated color temperature" (CCT); That is, the point (coordinates) that are not on the trajectory but not far away are also used as "color temperature", and the color temperature value is the value of the point closest to the trajectory.

In this way, the same color temperature, outside the trajectory, there are many points, and the lines of these points are called "isotherms"; That is, all the coordinates on this line have the same (correlated) color temperature.

Give a diagram. The numbers in the figure indicate the "isotherm", the curve is the "blackbody trajectory", and the ellipse is the coordinate range of the 6500k lamp specified by the state.

This is not possible to calculate the specific color temperature coordinates. Because this is not a corresponding, you can find his color temperature with one coordinate, but by color temperature he has many color temperature coordinates, "correlated color temperature" (cct); That is, the point (coordinates) that are not on the trajectory but not far away are also used as "color temperature", and the color temperature value is the value of the point closest to the trajectory.

In this way, the same color temperature, outside the trajectory, there are many points, and the lines of these points are called "isotherms"; That is, all the coordinates on this line have the same (correlated) color temperature.

Excuse me. I'm on a mission, and I don't know.

Color coordinates in all light sources.

The relationship with color temperature is shown in Fig

An LED color coordinate corresponds to a color temperature, and a color temperature corresponds to multiple color coordinates, that is, the excellent temperature can be calculated by the color coordinates, and the color temperature can only be found by the isotherm. The color temperature has an isotherm and a line corresponds to it in the chromaticity coordinates. A point in the chromaticity coordinate has only one color temperature value color coordinate, which is the coordinate of the color.

The color coordinates that are commonly used today are x on the horizontal axis and y on the vertical axis. With color coordinates, a point can be determined on a chromaticity map. This dot accurately represents the color of Lu Wei's glow.

The true color temperature (CT) is the color of light emitted by the black body when it is subjected to this temperature (k). A white color temperature du for a group of colors.

zhi coordinates. For example, a color temperature of 6250K, the color coordinates x= y= .

Temperature, from low to dao

high, the temperature points of each color form a (curved) line, which is called "black body color temperature trajectory".

However, what is often referred to as color temperature is actually "correlated color temperature" (CCT); That is, the point (coordinates) that are not on the trajectory but not far away are also used as "color temperature", and the color temperature value is the value of the point closest to the trajectory.

In this way, the same color temperature, outside the trajectory, there are many points, and the lines of these points are called "isotherms"; That is, all the coordinates on this line have the same (correlated) color temperature.

Give a diagram. The numbers in the diagram indicate the "isotherms", the curves are the "blackbody trajectories", and the ellipses are the national regulations, for example: the coordinate range of a 6500k lamp.

The relationship between color coordinates and color temperature in all light sources is shown in the figure.

In the figure: The line is within the "isotherm", that is, all the capacitance coordinates on the line are the same.

Number: The color temperature value of the line.

Ellipse: Six large and small ellipses are the range of color temperature and coordinates of the six kinds of light sources (2700K, 3000K, 3500K, 4000K, 5000K, 6500K) specified in China. The leftmost one is 6500K aperture, the large one is 6SDCM away from the center, and the small one is 5SDCM away from the center.

As long as it is in this aperture, no matter what its true color temperature is, it is called a 6500k lamp.

Color temperature is a block.

The lower the color temperature, the reddish color, and the higher the color temperature, the bluer color is right.

Generally, the color temperature of warm white light is 2200 3300K

Natural white is around 4000k.

True white is 4700 6500k

Cool white is greater than 7000k

First of all, correct a copy of the answer upstairs bai, the color temperature is not a du block on the chromaticity diagram, it is a line, that is, it is said that the LED with a color temperature value of dao, the color emitted is not necessarily the same, so it is necessary to introduce the value of color coordinates to accurately correspond to the color of an LED, especially the color of white light, each coordinate value only corresponds to a point on the chromaticity map, unlike a color temperature value corresponding to a line on the chromaticity map. But in the actual operation process, it is impossible to specify a coordinate value for the manufacturer to mass produce, the manufacturer will divide the color of a certain coordinate area into a region, and use letters such as ABCDEF to classify, and there are several small categories under each category, such as A1, A2, etc., after the white LED is produced, it will go through the spectrochromic machine and automatically filter to different categories.

Approx. 7690k.

method, see figure.

If you can't see clearly, tell me your mailbox.

Around 8300k. There are a variety of algorithms to calculate the color temperature from the color coordinates, and the calculated values are somewhat different from the actual values, the color coordinates are unique, but there are different coordinates under the same color temperature line, so there will be the same color temperature but different light colors. Why convert a definite value to an indeterminate value?

A few days ago, at the PhotonicsWest exhibition, Nichia, a major Japanese LED manufacturer, announced the laboratory results in early 2009, LED luminous efficiency increased to 249 lumens per watt at 20mA, but in the case of 350mA current, which is commonly used in the general LED industry, the luminous efficiency was reduced to 145LM W, which attracted the attention of the industry.

Takashi Mukai of Nichia said that the decrease in luminous efficiency caused by this change of current may be due to some problems in the manufacturing process. He pointed out that the efficiency of white LEDs can theoretically reach up to 263 lumens per watt, but if new fluorescent powder technology is used, Nichika can increase this limit to 300 lumens per watt.

Compared with the results of Nichika Laboratories, the luminous efficiency figure published by CRE, a major LED manufacturer in the United States, is 161 lumens per watt, while OSRAM is 136 lumens per watt, both of which are driven by a current of 350mA.

method, see figure.

If you can't see clearly, tell me your mailbox.

When a coordinate point is between two isotherms, the distance from the measurement point to the two straight lines is divided into the color temperature difference of the two isotherms according to the proportion of the two distances.

Suppose point A, between 6667K and 6250K, it is 3 cm away from 6667K and 7 cm away from 6250K.

then a color temperature = 6250 + 6667-6250)*7 (7+3)= 6250 + 292 = 6542