CN107166177A - A kind of adjustable LED artificial sun lights illumination system layout method of spectrum - Google Patents

Abstract

A design method for LED artificial sunlight lighting system with adjustable spectrum, the steps are: 1) designing a light source with adjustable spectrum, including LED light source module design and color temperature control algorithm design; 2) designing lighting optical system, including primary optical Design, spotlight system design, secondary light mixing design and diffuse reflection background light design. Based on the theory of non-imaging optics, the present invention designs an optical-mechanical-electrical-integrated optical system, which provides more design space and degrees of freedom for optical system design. Compared with traditional design methods, the idea of single-wavelength design is changed to multi-wavelength design. After the light source passes through the designed optical system, the light quality will be greatly improved; and through the design of the spectrum adjustable light source and the secondary optical design for the light source, two types of outgoing light can be obtained. One is the direct light similar to the solar spectrum. Light, the second is the diffuse reflection background light similar to space, and through the effective integrated optical system design, the uniformity of the diffuse reflection background light is cleverly solved, and the uniformity of the direct light is greatly improved.

Description

Design method of LED artificial sunlight lighting system with adjustable spectrum

technical field

The invention relates to the technical field of lighting devices, in particular to a design method for an LED artificial sunlight lighting system with adjustable spectrum.

Background technique

Semiconductor lighting (LED lighting) is the third light source revolution after incandescent lamps and fluorescent lamps. Due to its outstanding features such as high efficiency, energy saving, environmental protection, long life, and similar point light source, it is one of the most promising high-tech fields in the world in recent years. It has received strong support from major countries and regions in the world. At present, the global LED industry has entered the During the period of rapid development, the penetration rate of global LED lighting is rapidly increasing.

With the continuous improvement of the luminous efficiency of white LEDs, the space for improving luminous efficiency is further limited, and people's continuous pursuit of quality of life, light quality has begun to be valued, especially for indoor lighting, the requirements for light quality are far greater than the requirements for light efficiency. ;In addition, with social development, population growth, environmental changes and other factors, the working or living space of most people is compressed in a narrow indoor space, and natural light has gradually become a luxury. In this context, the development of high-quality artificial sunlight lighting devices has become an alternative solution that people urgently need. Among them, the research on lighting in Europe, America and Japan is greatly influenced by traditional sunlight, and in-depth research has been carried out here, and similar products have been formed. The DOE planning goal of the United States clearly realizes full-sunlight-like lighting by 2025.

Artificial solar lighting fixtures for producing natural light similar to illumination from the sun and sky, including: direct light sources and diffuse background light. In order to achieve this function, similar patents such as "artificial lighting device for generating natural light" with application number CN201280078131.0, and "artificial lighting with light emitter/collimator pair array" with application number CN201380070311.9 device". Although this series of patents has elaborated on the artificial sunlight lighting device, it has also carried out a relatively detailed visual design. However, there are still the following deficiencies: 1) The direct light used cannot be used for spectral control; 2) The background light formed by Rayleigh scattering from the diffuse reflection light source requires high technical requirements for the control of particles in the Rayleigh scattering plate; 3 ) The system does not involve the uniformity control method of outgoing light and background light; 4) The overall production scheme is complicated and the cost is high.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned problems and deficiencies, to provide an adjustable spectrum, simple production scheme, low cost, and through an effective optical solution, the diffuse reflection background light is uniform, and the uniformity of the direct light is greatly improved. Innovative LED artificial sunlight lighting system design method.

Technical scheme of the present invention is realized like this:

The spectrally adjustable LED artificial sunlight lighting system design method of the present invention is characterized in comprising the following steps:

Step 1: Design a light source with adjustable spectrum, including LED light source module design and color temperature control algorithm design; among them,

LED light source module design: According to the solar spectrum curve, select LED chips with different wavelengths, or select the same LED chip with different phosphor powder added to the surface, or select different LED chips with phosphor powder added to the surface to form an LED light source module;

Color temperature control algorithm design: First, calculate the proportion of each LED monochromatic light in the LED light source module according to the color temperature requirement, and then use an iterative optimization algorithm to obtain the proportion of each LED monochromatic light at the set color temperature, and use PWM dimming method to control Drive the output of each LED monochromatic light to obtain a stable and adjustable solar spectrum light source;

Step 2: Design the lighting optical system, including primary optical design, concentrating system design, secondary light mixing design and diffuse reflection background light design; among them,

One-time optical design: the design method is to control the shape of the silica gel, which is realized by opening the mold and pouring glue. The shape of the silica gel is a general hemispherical or cylindrical shape with a surface microstructure; or, the design method is to control the shape of the light guide, and the light guide is square Light pipe or light guide column; or, the design method is to use the shape control of silica gel and the shape control of light pipe at the same time; the purpose of this optical design is not only the traditional packaging function, but also the primary mixing of LED light source modules. The light and primary optical design can not only effectively uniform light, but also effectively control the light intensity distribution curve, providing more design space for secondary optical design;

Concentrating system design: the concentrating system is a TIR lens, and its outer surface is a free-form surface; or, the concentrating system is a combined optical system of a parabolic mirror and a Fresnel lens; the purpose of designing the concentrating system is to Control of divergence angle;

Secondary light mixing design: microstructure graphics design for pmma or pc optical materials; or, attach microstructure diffusion film on the surface of pmma or pc optical materials; the microstructure graphics are uniformly or randomly distributed, and the single microstructure graphics The height is 0.5-1.5um, and the diameter is 10-100um;

Diffuse reflection background light design: The diffuse reflection background light comes from the LED light source module, and the spectrum is selected through the filter; or, the diffuse reflection background light comes from the LED chip light source added inside the optical system.

Compared with the prior art, the present invention has the following significant advantages:

1) Based on the theory of non-imaging optics, the present invention designs an opto-mechanical-electrical integrated optical system, which provides more design space and degrees of freedom for optical system design. Compared with the traditional design method, the idea of changing from single wavelength design to multi-wavelength design makes the light quality of the light source greatly improved after passing through the designed optical system;

2) Through the design of the spectrally tunable light source and the secondary optical design for the light source, two types of outgoing light are obtained, one is direct light similar to the solar spectrum, and the other is diffuse background light similar to space. Moreover, through the effective integrated optical system design, the uniformity of the diffuse reflection background light is cleverly solved, and the uniformity of the direct light is greatly improved.

The present invention will be further described below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the lighting system of the present invention.

Fig. 2 is a schematic diagram of the arrangement of the light source module and the LED light source of the present invention.

Fig. 3 is a relative spectrum diagram of the present invention for outputting 6000K white light.

Fig. 4 is a schematic diagram of a square light guide in the primary optical and light mixing design of the present invention.

Fig. 5 is a schematic diagram of the simulation structure of the lighting system of the present invention.

Fig. 6 is an illumination diagram of outgoing light and a distribution diagram of light intensity with angle reflecting the simulation results of the lighting system according to the present invention.

Fig. 7 is a background light illuminance diagram and a distribution diagram of light intensity with angle reflecting the simulation results of the lighting system according to the present invention.

detailed description

The spectrally adjustable LED artificial sunlight lighting system design method of the present invention comprises the following steps:

Step 1: Design a light source with adjustable spectrum, including LED light source module design and color temperature control algorithm design; among them,

LED light source module design: According to the solar spectrum curve, select LED chips with different wavelengths, or select the same LED chip with different phosphor powder added to the surface, or select different LED chips with phosphor powder added to the surface to form an LED light source module;

Color temperature control algorithm design: First, calculate the proportion of each LED monochromatic light in the LED light source module according to the color temperature requirement, and then use an iterative optimization algorithm to obtain the proportion of each LED monochromatic light at the set color temperature, and use PWM dimming method to control Drive the output of each LED monochromatic light to obtain a stable and adjustable solar spectrum light source;

Step 2: Design the lighting optical system, including primary optical design, concentrating system design, secondary light mixing design and diffuse reflection background light design; among them,

One-time optical design: the design method is to control the shape of the silica gel, which is realized by opening the mold and pouring glue. The shape of the silica gel is a general hemispherical or cylindrical shape with a surface microstructure; or, the design method is to control the shape of the light guide, and the light guide is square Light pipe or light guide column; or, the design method is to use the shape control of silica gel and the shape control of light pipe at the same time; the purpose of this optical design is not only the traditional packaging function, but also the primary mixing of LED light source modules. The light and primary optical design can not only effectively uniform light, but also effectively control the light intensity distribution curve, providing more design space for secondary optical design;

Concentrating system design: the concentrating system is a TIR lens, and its outer surface is a free-form surface; or, the concentrating system is a combined optical system of a parabolic mirror and a Fresnel lens; the purpose of designing the concentrating system is to Control of divergence angle;

Secondary light mixing design: microstructure graphics design for pmma or pc optical materials; or, attach microstructure diffusion film on the surface of pmma or pc optical materials; the microstructure graphics are uniformly or randomly distributed, and the single microstructure graphics The height is 0.5-1.5um, usually set to 1um, and the diameter is 10-100um;

Diffuse reflection background light design: The diffuse reflection background light comes from the LED light source module, and the spectrum is selected through the filter; or, the diffuse reflection background light comes from the LED chip light source added inside the optical system.

The present invention will be further described below by specific examples.

Example 1:

1) According to the solar spectrum curve, select LED chips with different wavelengths to design the LED light source module. The specific design method is shown in Figure 2, including two blue LED chips, one green LED chip, and one red LED chip. LED chips and two types of white LED chips, each color LED chip is a narrow-spectrum LED monochromatic chip, and different chips are evenly arranged;

2) The optimal color temperature is 6000K, and the color temperature control algorithm is designed. First, according to the color temperature, the ratio of each LED monochromatic light is calculated, and then the iterative optimization algorithm is used to obtain the ratio of each LED monochromatic light at the set color temperature. Finally, PWM is used to adjust the color temperature. The light mode controls and drives the output of each LED monochromatic light to obtain a stable and adjustable solar spectrum light source. The spectrum diagram is shown in Figure 3.

3) An optical design is realized through the square light pipe, the purpose is to uniform light, so that after multiple total reflections of light of different wavelengths on the inner wall of the light pipe, the light intensity distribution curves of each wavelength tend to be consistent, and the illuminance distribution of the light outlet surface of the light pipe Uniform, the schematic diagram of the structure of the light guide is shown in Figure 4.

4) TIR lens is used as the concentrating system, and its outer surface is a free-form surface;

5) The secondary light mixing design is achieved by pasting the microstructured diffusion film on the pmma optical plate, and the microstructure is set facing outward;

6) Diffuse reflection background light design, the diffuse reflection background light comes from the LED light source module, and the spectrum is selected through the filter; the diffuse reflection of light is generated by multi-layer diffuse reflection film or volume diffusion material, so that the diffuse reflection light is dispersed Inside the lighting system, a sense of space is presented rather than simply diffuse light emitted from surfaces.

In order to verify the feasibility of this embodiment, the present invention uses the lighting design software Tracepro to model the structure of the lighting system of this embodiment, and perform light simulation. The simulation process is as follows:

1) Structural modeling, all modeled in the same proportion as required by this embodiment, the specific simulation structure diagram is shown in Figure 5; 2) Definition of material properties; 3) Definition of light sources according to the arrangement of light sources in this embodiment; 4) Monte Carlo ray tracing; 5) Analysis of simulation results.

In order to verify whether the light-emitting surface produces direct light, in the simulation model, a square detection screen is placed two meters away from the lighting system. The illuminance result is shown in Figure 6. The square-shaped light spot has a uniformity greater than 98% and a divergence angle of about 5. Spend.

In order to verify whether the light-emitting surface produces a diffuse reflection background while producing direct light, the light-emitting surface is selected as the detection screen, and the illuminance results are shown in Figure 7. Square-shaped light spot, the uniformity is greater than 90%, the divergence angle is about 60 degrees, and it is close to Lambertian light type.

The spectrum adjustable LED artificial sunlight lighting device designed by the present invention has a structure as shown in Figure 1, including an LED light source module 1, a primary light mixing device 2, a condenser lens 3, a secondary light mixing device 4, a diffuse Reflective background light generating system 5 and light exit surface 6 .

The present invention is described by the embodiment, but does not constitute limitation to the present invention, with reference to the description of the present invention, other changes of the disclosed embodiment, if it is easy to imagine for those skilled in the art, such changes should belong to Within the scope defined by the claims of the present invention.

Claims (1)

1. A design method of a spectrum-adjustable LED artificial sunlight lighting system is characterized by comprising the following steps:

the method comprises the following steps: designing a light source with adjustable spectrum, wherein the light source comprises an LED light source module design and a color temperature regulation algorithm design; wherein,

designing an LED light source module: selecting LED chips with different wavelengths, or selecting the same LED chip with different fluorescent powder added on the surface, or selecting different LED chips with fluorescent powder added on the surface to form an LED light source module according to a solar spectrum curve;

designing a color temperature regulation algorithm: firstly, calculating the proportion of each LED monochromatic light in an LED light source module according to the color temperature requirement, then obtaining the proportion of each LED monochromatic light at the set color temperature by adopting an iterative optimization algorithm, and controlling and driving the output of each path of LED monochromatic light by adopting a PWM dimming mode to obtain a stable and adjustable solar spectrum light source;

step two: designing an illumination optical system, wherein the illumination optical system comprises a primary optical design, a light condensing system design, a secondary light mixing design and a diffuse reflection background light design; wherein,

primary optical design: the design mode is that the shape of the silica gel is regulated and controlled, and the regulation and control are realized by opening the die and pouring the silica gel, and the shape of the silica gel is a universal hemisphere or a cylinder with a surface microstructure; or the design mode is that the shape of the light pipe is regulated, and the light pipe is a square light pipe or a light guide column; or the design mode is that the silica gel shape regulation and control and the light pipe shape regulation and control are used simultaneously; the primary optical design aims at the primary light mixing and primary optical design of the LED light source module besides the traditional packaging function, so that not only can effective light uniformization be carried out, but also the light intensity distribution curve can be effectively regulated and controlled, and more design space is provided for the secondary optical design;

designing a light condensing system: the light condensing system is a TIR lens, and the outer surface of the light condensing system is a free-form surface; or the light-gathering system is a combined optical system of a parabolic reflector and a Fresnel lens; the light condensing system is designed for regulating and controlling the light ray direction and the divergence angle;

designing secondary light mixing: carrying out microstructure pattern design on a pmma or pc optical material; or, pasting a microstructure diffusion film on the surface of the pmma or pc optical material; the microstructure patterns are uniformly or randomly distributed, the height of each single microstructure pattern is 0.5-1.5 um, and the diameter of each single microstructure pattern is 10-100 um;

designing diffuse reflection background light: the diffuse reflection background light comes from the LED light source module, and spectrum selection is carried out through the optical filter; alternatively, the diffuse reflection background light originates from an LED chip light source added inside the optical system.