LedRise LED Lighting Blog

Human Centric Lighting (HCL) is an illumination specially designed to have a positive physiological and/or psychological effect on humans. It consists of adjusting the colour and intensity of the light throughout the day using adjustable white LED lighting solutions.

HCL supports human health, well-being and performance by considering and properly planning the implementation of a lighting system according to the desired visual, emotional and above all biological effects of light. Human Centric Lighting focuses on the needs of people for their living, leisure and working environment. The study is based on the properties and effects of natural light, a dynamic source of changing tone and brightness that changes throughout the day and seasons. 

A combination of white LED light sources, usually warm white (2700K) and cold white (6500K), is used to provide adequate human-centred lighting. This solution is also called Tunable White lighting. By adjusting the intensity of each individual, bright or dull white light with a hue between 2700K and 6500K can be achieved. It is a new way of using and implementing artificial light, corresponding to the changes of natural light and research on the effects on humans.

The positive health effects of the uniform spectral power distribution of the SunLike LEDs from Seoul Semiconductor have been confirmed in two independent studies, by universities from Switzerland and South Korea.

The new SunLike technology brings a major improvement to the LED spectral power distribution (SPD) which now mimics the SPD of the sun within the bounds of the human visual range. The SunLike LEDs LEDs use a three-phosphor mix and a violet emitter to achieve the SPD. Seoul has said that the LEDs can be used in a variety of applications including in human-centric lighting or lighting for health and well-being where tunable lighting can be applied to improve human well-being.

A study published by the University of Basel in Switzerland titled “Effect of daylight LED on visual comfort, melatonin, mood, waking performance, and sleep” found that volunteers had better visual comfort, more alertness, and happier moods associated with exposure to SunLike LEDs  compared LEDs. 

The university published the research in the Journal of Lighting and Research Technology. Professor Christian Cajochen led the research team investigating what they referred to as LEDs with a daylight spectrum.

Careful design of the lighting for your home will ensure that the right amount of light is where and when needed, switched on conveniently. Lighting should avoid over-lit areas, and give control and flexibility to create lighting effects for different situations. Well-designed lighting will be inherently easier to use and will function in an energy-efficient way.

The best approach to home lighting design is to use three levels of lighting: general lighting, task lighting and accent lighting. By combining these three levels, the recommended lighting level for each room or activity should be obtained, as below: 

The three levels of lighting

General lighting should ensure a sufficient minimum level of light in the room. There are plenty of LED light sources that can be used for this purpose: LED modules, strips, luminaries or spotlight. Decide on the desired illuminance level (lux). In living rooms and bedrooms in particular, give a certain degree of flexibility (through control settings/dimmers) so that occupants can raise or lower the general lighting around the set level. Design for the upper end of the Lux ranges in homes with elderly occupants, which generally appreciate a higher level of general lighting. A minimum level of general lighting is required for safe movement in the home, especially on the stairs, but sufficient general LED lighting is considered important for general well-being.

Workplace lighting is needed for certain activities at home, such as reading, preparing food and working from home. LED lamps must be carefully selected, correctly positioned and controlled. Recommended are LED spot lights and high flux LED modules. Lamps or sockets are needed in the right places to ensure flexibility in the availability of work and accent lighting. Depending on the task, LED workplace lighting may be required at different levels. The color rendering of the light is also very important for some activities, we recommend LED lights with CRI 97 or more.

Accent lighting contributes to the ambiance of a house and is usually done with LED spots and strips. As with workplace lighting, LED luminaires (or sockets) are placed in the right places to emphasize architectural features, furniture and ornaments. Accent lighting is a more personal matter, and depending on the circumstances, spotlighting or floodlighting can be useful.

For each of these levels of lighting, controls can provide a range of lighting options. So in an living room there could be separate controlled circuits for:

• general lighting 
• task lighting (typically positioned under the wall units) 
• accent lighting 

Similar control patterns can be considered in other rooms, with dimmers providing a different lighting atmosphere in salons, dining rooms and bedrooms. Advanced controls, sometimes controlled by a mobile phone or a tablet app, that allow remote adjustment of the amount of light and its color are increasingly popular. Lighting is establishing itself as a lifestyle statement, and houses with new and innovative lighting systems are perceived as a marketing advantage.

The innovative Optisolis LEDs from Nichia have a light spectrum that closely matches the spectrum of natural sunlight.

Luminous efficacy measures how effectively a light source produces visible light. With LEDs and other light sources, luminous efficacy is the ratio of luminous flux to electrical power, known as lumens per watt (lm/w). For example, the light output (luminous flux) of a 1 Watt LED can be very bright for high efficacy or barely visible for low.

The luminous efficacy is one of the defining factors of LED performance. Top performance LEDs, with the highest luminous efficacy, have 220 lumens per watt (lm/w), such as the Nichia 757G LEDs. High performance LEDs, like those from many other manufacturers, have 150-200 lm/w. At the far end, we have the low cost, poor performance LEDs with an efficiency of less than 99 lumens per watt.

For residential applications, LED lights with a CRI of at least 90 are recommended for bedrooms, living rooms, bathrooms, and kitchens. For business applications, lights with a CRI of 80 are suitable for general work in offices, while lights with a CRI of 97 are recommended for offices where work with colors is involved, as well as design studios and photography studios. For commercial applications, LED lights with a CRI of 90 or higher are recommended for electronics stores, hardware stores, and jewelry stores, while lights with a CRI of 98 are ideal for interior design stores.

Introducing Nichia Optisolis LEDs: Harnessing the Full Spectrum of Sunlight for Various Applications

The world market leader in LED development, Nichia, has unveiled its latest innovation: the Optisolis™ technology. Optisolis™ LED emitters provide a natural light source with a spectrum that achieves the industry's closest match to that of standard illuminants, sunlight, and incandescent artificial light, boasting a color rendering index (CRI) of over 98.

The Optisolis family of LEDs are classified as Ultra-High CRI light sources, as they have maximum scores for all 16 color samples used in the color rendering index metric. The 5000K Nichia NF2L757G-F1 Optisolis LED can even achieve a Ra of 99 out of 100. Similarly, the scores with the new IES TM-30-15 light quality tests are equally high, with Rf at 98 and Rg at 99.

Illuminated stretch ceilings are an innovative lighting design solution that has gained popularity in recent years. They offer a wide range of advantages over traditional lighting systems, including uniform illumination, a relaxing ambiance, and minimal glare. Additionally, they can be used for a variety of lighting purposes, such as ambient lighting, general lighting, and even workplace lighting.

However, designing and installing an illuminated stretch ceiling can be a challenging task, and it is essential to take various factors into consideration to ensure optimal results. One of the most important factors to consider is the choice of materials, as the translucency of the stretch ceiling material plays a crucial role in determining the light transmission rate and overall illumination quality. The choice of lighting source is also crucial, as it can affect both the brightness and the energy efficiency of the stretch ceiling.

Another essential aspect to consider is the optimum distance between the LEDs and the stretch ceiling. To ensure even illumination, the LEDs must be evenly distributed behind the translucent material. Therefore, the distance between the light sources and the stretch ceiling should be at least 30 cm to a maximum of around 50 cm, depending on the type of LED used.

The shape of the illuminated stretch ceiling is also an essential factor to consider. It can be personalized and feature translucent images, which can greatly influence the overall design of the space. Additionally, spotlights or lamps can be used to highlight specific areas or objects, complementing the uniform light of the illuminated stretch ceiling.

Introduction to the Color Rendering Index (CRI)

In 1974, the International Commission on Illumination (CIE) introduced the Color Rendering Index (CRI) to compare the color rendering of artificial light sources to a reference standard illuminant modeled after daylight. The CRI aimed to express the quality of white light produced by various types of gas lamps available in the market at that time.

Over the past 40 years, the CRI index has become deeply ingrained in the lighting industry and among professionals. However, it remained relatively unknown to most consumers since it wasn't particularly relevant to their decision-making when purchasing lighting. Manufacturers produced most lamps based on their CRI value for specific applications, ensuring that the choice of lamp could not be wrong. For instance, office or linear lighting typically used Tri-Phosphor linear fluorescent tubes with a CRI over 80. Homes relied on incandescent lamps and halogens with a CRI of 100, while retail spaces utilized metal halide lamps with a minimum CRI of 85.

The makeup of some fixture types for common applications, such as down-lighting, spot-lighting, office-lighting and street-lighting. All can use LEDs.

Seoul Semiconductor’s SunLike Series, equipped with TRI-R technology, represents a groundbreaking advancement in LED lighting. These true natural spectrum LEDs produce light that closely emulates the spectrum of natural sunlight, thanks to a novel LED architecture. By using a purple emitter combined with a red, green, and blue (RGB) phosphor mix, SunLike LEDs offer significant improvements over conventional white LEDs, which rely on a blue emitter and yellow phosphor.

This innovative approach to full-spectrum LED lighting results in accurate color rendering, heightened awareness of contrast and texture, and an overall superior visual experience. In this article, we will delve into the unique properties of SunLike LEDs and their applications in art and museum lighting, which are truly transformative.