LED的照明控制，第四部分：LED照明的颜色控制

***以下内容为 照明172-14-康余多 翻译***

**WHY THE USE OF COLOR IN LIGHTING IS EXPANDING**

**为什么在照明中使用颜色越来越多**

Solid-state lighting opens doors to use of color beyond the capabilities of conventional technologies. Unlike the use of fixed color bulbs with filters mechanically added, LED products can generate virtually any color perceivable by the human visual system, as well as any shade of white, all digitally controlled and selectable.Full color effects have grown beyond entertainment and decoration to include mood setting, and environmental enhancement. Here are just a few of the growing number of uses for controlled color lighting systems:

固态照明开启了使用传统技术所不能达到的颜色的大门。不像使用固定的彩色灯泡与过滤器机械地添加，LED产品几乎可以产生任何人类视觉系统可以感知的颜色，以及任何白色阴影，所有数字控制和选择。

全彩效果已经超越了娱乐和装饰，包括情绪设置和环境改善。以下是其中的一些控制颜色照明系统的使用越来越多:

**·White light tuned in concert with intensity to suit a desired mood (from warm candlelight at low levels to brilliant cool white to match sunlight).**

**·Change of light character to match seasonal displays in retail applications.**

**·Daylight simulation to support / enhance circadian rhythm function, ramping both intensity and white light color to match natural light effects.**

**·Plant and agricultural lighting that changes in spectral power (blue and red light rich) to support plant health and growth, changing to white light when spaces are shared and occupied by humans.**

**·Light color and intensity to imitate tropical regions to support reef fish tanks in large displays, or in reproduction centers for aquatic farming.**

**·Wildlife sensitive color in coastal regions that change from white light in normal modes to amber light during hatch and critical periods to avoid interference of natural cycles affected by artificial visible light.**

**·Adjust light color from different luminaires to a uniform standard, or to adjust color over the life of products.**

**·Deliver white light and color effects lighting from the same lighting system.**

**·Theatrical applications, eliminating the need for redundant lighting products by applying one single system capable of delivering all desired colors, including white, controlled centrally.**

**·白光与强度协调一致，以适应所需的情绪(从温暖的烛光低水平，以配合阳光灿烂的冷白色)。**

**·改变灯光特性以配合零售应用中的季节性显示。**

**·日光模拟，以支持/增强昼夜节律功能，倾斜强度和白光颜色，以匹配自然光的效果。**

**·植物和农业照明，即光谱功率的变化(蓝光和红光丰富)，以支持植物的健康和生长，改变为白光时空间由人类共享和占据。**

**·浅色和强度模仿热带地区的暗礁养鱼池进行大型展示，或在繁殖中心进行水产养殖。**

**·沿海地区野生动物敏感的颜色，在孵化和关键时期由正常模式的白光变为琥珀色受人造可见光影响的自然循环的干扰。**

**·调整不同灯具的光色到一个统一的标准，或调整产品寿命的颜色。**

**·提供来自同一照明系统的白光和彩色效果照明。**

**·戏剧应用，通过应用一个能够提供所有所需颜色的单一系统，消除了对冗余照明产品的需求，包括白色，中央控制。**

### LED RGB COLOR MIXING

Mixing color LEDs can generate millions of colors of light, including white, simply by mixing red, green and blue (RGB) LEDs in various relative intensities controlled via dimming.

LED RGB混色

混合颜色led可以产生数百万种颜色的光，包括白色，只需混合红色，绿色和蓝色(RGB) led在不同的相对强度通过调光控制。

### COMPOUNDING COLORS TO CREATE WHITE LIGHT

While simply mixing red, blue and green light can produce white light, true color accuracy requires a more complete distribution of color wavelengths in the light. Color LED sources produce a very narrow spectral power distribution, resulting in gaps between each discrete color that causes errors in white light color accuracy. By adding colors and white into the mix, we can achieve a wider range of whites and near-white colors with greater fidelity and depth. Additionally, more colors reduces gaps in the white light spectrum, which improves color rendering. The tradeoff is cost; each color requires a separate driver so increasing the number of colors increases total system and related control costs.

混合颜色产生白光

虽然简单地混合红色，蓝色和绿色的光可以产生白光,真正的色彩精度需要- - -个更完整的分布在光的颜色波长。彩色LED光源产生非常窄的光谱功率分布，导致每个离散的颜色之间的差距，导致白光色彩精度的误差。通过添加颜色和白色的混合，我们可以实现更大范围的白色和接近白色的颜色与更大的保真度和深度。此外，更多的颜色减少了白光光谱中的空白，从而提高了显色性。权衡就是成本;每一种颜色需要单独的驱动程序，因此增加颜色的数量会增加整个系统和相关的控制成本。

### WHITE LIGHT TUNING AND MIXING

Mixing white light of different color temperatures presents a tunable palette of white light. One approach is to simply combine warm and cool white LEDs, which allows a range of color tones between the two extremes. The mix of two white sources, however, cannot produce spectral power that neither produces, so a small shift toward magenta may occur in the blended regions while the black body line arcs (see graphic). In addition to mixing two white light sources, the use of blue and amber LEDs can be employed with a white light LED to create a warmer or cooler color white light.

白光调谐和混合

混合不同色温的白光呈现出一个可调的白光调色板。一种方法是简单地将暖白色和冷白色结合起来发光二极管，允许在两个极端之间的色调范围。然而，两种白色光源的混合不能产生那样的光谱功率两者都不产生，所以当黑体线呈弧形时，在混合区域可能会发生向洋红色的小转变(见图)。除了混合两个白光光源，使用蓝色和琥珀色的LED可以与白光LED一起使用，创造一个更温暖或更冷的白光颜色。

### INTEGRATED CLOSED-LOOP COLOR CONTROL (WHITE)

All LEDs suffer some lumen depreciation and color shift as they age. Over time, phosphors used in white LEDs gradually decline in their ability to generate warm colors, causing a gradual trend toward a cooler color tone. This occurs more rapidly when exposed to high ambient temperatures.This color shift may be mitigated using an onboard color management system that uses special LED mixes of yellow-green and red-orange to generate white light, continually balanced by feedback loop computer control to maintain high color rendering and the desired color tone.

集成闭环颜色控制(白色)

所有的led在老化过程中都会出现流明下降和颜色变化。随着时间的推移,白色led中使用的荧光粉产生暖色的能力逐渐下降，导致色调逐渐变冷。这当暴露于较高的环境温度时，发生得更快。这种颜色的变化可以通过机载的颜色管理系统来缓解，该系统使用了黄绿红橙混合的特殊LED产生白光，通过计算机反馈回路控制持续平衡，以保持高的显色率和所需的色调。

### INTEGRATED CLOSED-LOOP COLOR CONTROL (MIXED COLOR)

Luminaires that employ a combination of colors require sophisticated control and individual drivers for each color to maintain a desired color temperature as LEDs age and ambient temperatures fluctuate. Through the use of continuous closed-loop optical feedback, the balance of RGB output can be balanced to maintain the specified color mix, thereby increasing color consistency both luminaire to luminaire and over time.

综合闭环色彩控制(混色)

当led老化和环境温度波动时，采用多种颜色组合的灯具需要复杂的控制和每种颜色的单独驱动程序来保持所需的色温。通过使用连续的闭环光学反馈，RGB输出的平衡可以被平衡，以保持指定的颜色组合，从而增加灯具与灯具之间的颜色一致性且不随时间变化。

### CONTROLLING INTENSITY

Whether adjusting the intensity of a single light source or dimming a combination of LEDs to generate a desired shade of white or create a color using RGB blending, the core component is dimming. This can be accomplished by direct voltage control, adjusting current settings or through pulse-width modulation (see Part 1 of this course). PWM and PAM controls operate at a very high frequency, adjusting current flowing through the LEDs to create predictable dimming performance necessary for creating color mixes and achieving uniform dimming.

控制强度

无论是调整单个光源的强度，还是调暗led组合以生成所需的白色阴影，还是使用RGB混合创建颜色，核心组件都是调光。这可以通过直接电压控制、调整电流设置或脉冲宽度调制来实现(参见本课程第1部分)。PWM和PAM控制运行在一个非常高的频率，调节电流通过led创建可预测的调光性能所需的创建混合颜色和实现均匀调光。

### CHALLENGES WITH COLOR CONTROL

Mixing colors to create special effects, warm or cool white light, or any combination requiring more than simple overall intensity control can become quite complex as more colors are added to the system. The intensity of one color is controlled easily with a simple wall station control. Addition of a second white to provide warm-cool balance and blending—plus intensity—requires at least two controls. Control of RGB for color mixing plus intensity requires four. Obviously, if the goal is to attain consistent and uniform color, conventional manual wall station controls are inadequate to the task.

色彩控制的挑战

混合颜色来创造特殊效果，温暖或冷白光，或任何需要比简单的整体强度控制更复杂的组合，可以成为相当复杂的颜色添加到系统。一种颜色的强度很容易控制与一个简单的墙站控制。添加第二种白葡萄酒以提供冷暖平衡和混合——加上强度——至少需要两个控制。控制RGB的色彩混合和强度需要四个。显然，如果目标是达到一致和统一的颜色，传统的手动墙站控制是不够的任务。

### COLOR CONTROL SOLUTION

One solution to these challenges is to use a microprocessor-based controller that can manage the mix of color, interpret the input provided by the end-user and additional sensors, and offer memory presets that allow colors to be chosen, stored and recalled.Providing the most user-friendly interaction with LED products with enhanced color selection features requires a control system that combines the color and intensity control functions, interfaces with remote sensing, and communicates directly with luminaires.

Interfaces that deliver intuitive color mixing, intensity control and memory preset recall enables lighting users to easily access the capabilities of mixed LED color systems consistently and predictably.Additional control interfaces through a computer as well as portable smart devices—e.g., phones and tablets—expand the potential for attaining exciting results that would otherwise be cost-prohibitive or too complex for manual control.

颜色控制解决方案

解决这些挑战的一个方法是使用一个基于微处理器的控制器，它可以管理颜色的混合，解释由终端用户和额外的传感器，并提供记忆预设，允许颜色的选择，存储和召回。

提供最用户友好的互动与LED产品与增强的颜色选择功能，需要一个控制系统，结合的颜色和亮度控制功能，与遥感接口，并直接与灯具通信。

界面提供直观的颜色混合，强度控制和记忆预置回忆，使照明用户能够轻松地访问混合LED颜色系统的能力一致和可预测的。

通过计算机以及便携式智能设备提供额外的控制接口。，电话和平板电脑——扩大了获得令人兴奋的结果的潜力，否则成本高昂或过于复杂的手动控制。

### UNIVERSAL COLOR CONTROL: DMX512A

The most widely applied control protocol for color LED products—full color effects or white tuning—is DMX512A. This protocol is typically used in theatrical and entertainment applications, though it is flexible and adaptable to architectural applications.

DMX512A is based on a Class 2 RS485 serial bus that uses XLR Style 5 pin connectors (basic F+DMX requires only three of these) or Cat 5 Ethernet cabling with 8P8C connectors (similar to RJ45). The bus speed is relatively slow at a rate of 250 kbaud. Luminaires are connected in a series daisy chain with a termination resistor installed on the last luminaire.Each connected luminaire is assigned a unique three-digit address either by 1) software based on location in the daisy chain, DIP switches or dials in the luminaire, or 2) an electronic addressing module in the luminaire or in the system. The software will allow grouping to respond to identical settings. While no two luminaires share the same address, they may be grouped as a single load outside the DMX universe and assigned to a dimmer that is part of it.

Up to 32 channel addresses can be connected in each control loop or channel. Each color is an RGB luminaire. Each color in an RGB luminaire is considered a separate address within the channel, so the number of luminaires per channel is reduced to 10. Additional luminaires can be connected to a loop using a repeater or through a DMX control splitter to maintain signal intensity. DMX controls can also be operated from wireless networks from a growing number of providers.At the next higher level, a group of 512 channels (control loops) is called a “universe.” The number of universes available in any system depends on the control manufacturer and is not limited by the protocol. The definition of 512 is simply the limit of three-digit numeric identification using 8-bit binary addressing (8 x 8 x 8 = 512).

通用色彩控制:DMX512A

应用最广泛的彩色LED控制协议产品——全彩效果或白色调谐——DMX512A。该协议通常用于戏剧和娱乐应用程序，尽管它对于体系结构应用程序具有灵活性和适应性。

DMX512A是基于一个类2 RS485串行总线，它使用XLR风格的5针连接器(基本的F+DMX只需要其中的三个)或Cat 5以太网电缆与8P8C连接器(类似于RJ45)。总线速度相对较慢，为250kbaud。灯具通过安装在最后一个灯具上的终端电阻连接在一个串接的菊花链上。

每个被连接的灯具都被分配一个独特的三位地址:1)基于菊花链的位置的软件，在灯具中的DIP开关或刻度盘，或2)灯具或系统中的电子寻址模块。该软件将允许分组响应相同的设置。虽然没有两个灯具共享相同的地址，但它们可能被分组为DMX宇宙之外的单个负载，并被分配给DMX宇宙中的一个调光器。

在每个控制回路或通道中最多可连接32个通道地址。每个颜色是一个RGB灯具。RGB灯具中的每一种颜色都被认为是通道内的一个独立地址，因此每个通道的灯具数量减少到10个。可以使用中继器或通过DMX控制分配器将附加灯具连接到环路上，以保持信号强度。DMX控件还可以通过越来越多的供应商提供的无线网络进行操作。

在更高一级，一组512通道(控制循环)称为“宇宙”。在任何系统中可用的宇宙的数量取决于控制制造商，不受协议的限制。512的定义仅是使用8位的三位数字标识的极限二进制寻址(8 x 8 x 8 = 512)。

### DMX512 BASICS

DMX512 is a digital protocol. It divides light level from 0% to 100% in 256 steps (based on the 8-bit binary code limitation of the number of 1+0 combinations available). For greater resolution, two DMX channels may be used together to yield a 16-bit code, resulting in a potential resolution of 65,536 steps. However, for most applications, the basic 256 steps of intensity control are more than adequate.The controls interface generates a binary code packet. The controller first sends out a reset signal referred to as the break. This is followed by a special number called the start code. The number following the start code is the level for channel one, then the level for channel two, etc. This series of numbers continues until the console runs out of assigned channels in the universe, upon which additional code is sent to reset the timing of the universe, and then it is repeated, refreshing the setting for each assigned channel. Each universe in a multi-universe system operates independently. How this is coordinated is determined by the manufacturer of the DMX controls system.For single-function products (dimming only), each luminaire will be assigned one channel address. For multiple color products, each luminaire will be assigned additional channel addresses in sequence. For example, the first luminaire in an RGB control loop will be assigned addresses 1, 2 and 3, the next 4, 5 and 6. Control of the individual channels (colors and luminaires in this case) are managed in the software selected to control the system installed.No automatic error checking: DMX 512 is a one-way control protocol, sending information outward to channels only, with no feedback loop to verify an action has been taken or reporting luminaire status. This means that this protocol is unsuitable for use in life safety applications where notification of a control failure or luminaire failure is necessary. However, within DMX512-A, it is possible to include diagnostic feedback through RDM (Remote Device Management) functionality for luminaire and controls provides, should they choose to take advantage of it.

DMX512基础知识

DMX512是一种数字协议。它将光级从0%到100%划分为256步(基于1+0组合的8位二进制代码限制)。为了获得更高的分辨率，可以将两个DMX通道一起使用以生成16位代码，从而获得65,536步的潜在分辨率。然而，对于大多数应用来说，256个基本的强度控制步骤已经足够了。

控件接口生成一个二进制代码包。控制器首先发出一个复位信号，称为中断。然后是一个特殊的数字，称为开始代码。开始代码后面的数字是通道1的级别，然后是通道2的级别，以此类推。这个数字系列将一直持续下去，直到控制台耗尽宇宙中分配的通道，然后发送额外的代码来重置宇宙的计时，然后重复此过程，刷新每个分配的通道的设置。多宇宙系统中的每个宇宙都是独立运行的。如何协调由DMX控制系统的制造商决定。

对于单功能产品(仅调光)，每个灯具将被分配一个通道地址。对于多种颜色的产品，每个灯具将按顺序分配额外的通道地址。例如，RGB控制循环中的第一个灯具将被分配地址1、2和3，接下来分配地址4、5和6。控制个别通道(颜色和灯具在这种情况下)是管理的软件选择来控制安装的系统。

无自动错误检查:dmx512是一种单向控制协议，仅向通道发送信息，没有反馈回路来验证操作是否完成或报告灯具状态。这意味着本协议不适合在需要通知控制故障或灯具故障的生命安全应用程序中使用。但是，在DMX512-A中，可以通过RDM(远程设备管理)功能为灯具和控制器提供诊断反馈，如果他们选择利用它的话。