Lumistrips LED Lighting Blog

The CRI, colour rendering index, is a one-number quantification that indicates the performance of an artificial light source in terms of colour rendering compared to a reference standard light source modelled on daylight. The highest number is 100, for daylight and incandescent/halogen lamps, while gas discharge lamps range from 17 to 96, with even a negative value for low sodium pressure (the yellow type used in street lamps).

Due to this variation in the ability to reproduce colour with the white light emitted by the many types of gas lamps on the market, CRI index was introduced in 1974 by the International Commission on Illumination (CIE). 

Today, with more than 40 years of use, the CRI index is firmly rooted in the lighting industry and among professionals. However, it has not been very well understood by the public. The reason was that such knowledge was not really useful as most lamps were built for specific applications that required a minimum CRI value, so one could not go wrong when choosing a lamp.

For example, for office or other linear lighting, the lamps of choice where Tri-Phospor linear fluorescent tubes on the market since the 1970s, all with a CRI value above 80. For domestic lighting, there was a mix between incandescent and halogen lamps, both with CRI100, for retail and other high intensity spot lighting, metal halide lamps with CRI min 85. Street lighting was reserved for high intensity and very efficient sodium vapour lamps, which had a poor CRI but this was considered not important.

From the year 2000 this changed with LED technology, the first light source that can be used for any application while having a broad performance and quality level, including the ability to reproduce colours accurately. It is therefore essential that you choose LEDs with the right CRI level for your application.

The picture above shows how colors can look different based on the CRI of the light source that illuminates them. A vibrant red under sunlight or a high CRI light can look dull or even orange under a low CRI light.

Growing plants in closed and fully controlled environments under artificial lighting has become increasingly popular in recent years. As competition intensifies, the demand for low-cost, high-speed results has placed a significant focus on the efficiency of lighting systems. In this comprehensive guide, we'll walk you through the essential steps to create an efficient and cost-effective lighting system for optimal plant growth.

1. Research the Spectrum and Intensity of Light Your Plants Need

The first step in designing an efficient lighting system is to determine the appropriate spectrum and intensity of light required for your specific plants. Different plants have varying needs in terms of light spectrum and intensity for optimal growth. To learn more about horticultural lighting, read our detailed article [here].

2. Choose the Right Photosynthetic Photon Flux Density (PPFD) and Light Color for Your Plants

With advancements in technology, special or full-spectrum white light LEDs have emerged as the most efficient and cost-effective light sources for plant growth. Our full-spectrum/Rsp0a CRI98+ LED strips will help your plants grow up to 50% more than conventional light sources, such as standard white LEDs, a combination of red and blue LEDs, or fluorescent tubes, while consuming less energy.

Selecting the appropriate color temperature is also essential. A 3000K white color temperature results in more aesthetically pleasing plants, while a 5000K color temperature promotes faster growth.

The Lumistrips LumiFlex3098+ LED strips uses true natural spectrum LEDs from Seoul Semiconductor’s SunLike Series with TRI-R technology, to emit light that closely matches the spectrum of natural sunlight. Full spectrum light is made possible by using a new LED architecture, with a purple emitter in combination with a red, green, and blue (RGB) phosphor mix, unlike conventional white LED that use a blue emitter and yellow phosphor. 

This new approach to full spectrum LED lighting has the effect of accurate rendering of colors, almost as daylight, with the added benefit of increased awareness of contrast and texture. 

With the unique quality of the light spectrum, SunLike LED fixtures are perfect for lighting art, such as paintings, frescoes, mosaics, sculptures and many other exhibits, both in museums and private residences.

Lumistrips Lumiflex3098+ SunLike LEDs reveal more color and texture for exquisite works of art, in private collection

The uniform spectral power distribution enabled by a three-phosphor mix of the Lumistrips Lumiflex3098+ SunLike LEDs now naturally light the exquisite works of art such as statues, pottery and art glass in a private collection, showcased in a residential home in Europe. The LEDs now ensuring that residence and guests will fully experience the item's color and texture.

A Cove light is a line of light can obtained via a LED strip hidden from view inside a cove in the wall or ceiling that illuminates an adjacent surface. Light is reflected from this surface into the space that has to be illuminated. That is why lines of light are commonly known as cove or indirect lighting.

Cove lighting is beneficial trend to design lighting, with focus on human nature and how natural light behaves. It is today widely adopted, with lines of light as a principal way to illuminate interiors.

The allure is the similarity with natural light. With the proper light source used, we could imagine that the cove is actually a hidden window to the outside from where sunlight flows in.

Lets explore how we can have the best results with cove lighting

Good design of your home lighting will ensure that the right amount of light can be switched on conveniently and will light where and when it is needed. A proper home 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 more likely be energy-efficient.

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

The three levels of lighting

General lighting should ensure a sufficient minimum level of light in the room. There are many LED light sources that can be used for this purpose: LED modules, strips, luminaries or spotlights. Decide on the desired illuminance level (lux). In living rooms and bedrooms give a certain degree of flexibility (through control settings/dimmers) so...

Casambi, a pioneer in Bluetooth Low Energy (BLE) wireless lighting control, has teamed up with LED technology specialist Seoul Semiconductor to offer lighting designers precise control of LED strips, modules and luminaires that use the new SunLike technology that matches the spectrum of sunlight. For the first time, this development puts true human-centered lighting in the hands of designers.

Users can use Casambi's Bluetooth-based wireless control system and app with products that include SunLike series LEDs to precisely adjust the light level, knowing that the spectrum reflects real sunlight, a key ingredient for Human-centric lighting

Human-centric lighting describes lighting designed to work with the natural rhythms of the human body. It is based on the well-known fact that the human eye recognizes the presence of a certain wavelength of blue light in the spectrum of sunlight and derives the time of day from this. In this way, light helps to regulate our sleep-wake cycles and other physical rhythms and has a significant impact on our mood and well-being.

Human-centered lighting takes advantage of this effect by adjusting its brightness and color temperature during the day to mimic natural light.

Casambi allows control of the lights through a timer or a variety of presence/movement sensors and daylight sensors. It can control lights that change colour temperature over a very wide range, and designers have the freedom to configure dimming and create scenes or animations for the application.

Natural light is white light which is not static but a dynamic source with changing tone and brightness, as a day goes by and seasons change. The tone of white light is called color temperature and is express in degrees Kelvin (K).

The color temperature of daylight changes during the day, from 2000K at sunrise and sunset to 5500-6500K at noon. In the shade in can even go to 8000-10000K.

Artificial light sources are available with all relevant color temperatures of sunlight. Some of them, such as incandescent lamps, can be produced with only one color temperature: 2700K. LEDs are light sources that can be produced with all color temperatures from 2000K to 10000K, while the most are found in the 2700-6500K range.

The CRI is a number quantification of the ability of the artificial source of reproducing colors, compared with reference standard illuminant modeled after daylight.

It was introduced by the International Commission on Illumination (CIE) in 1974, because of the wide variation in the ability to reproduce colors with the white light emitted by the many types of gas-lamps then on the market. Today, with over 40 years of use, the CRI index is firmly rooted in the lighting industry and among professionals.

From 2000s onward, LED technology has exposed the limits of the CRI index test method.

LED is the first lighting source that can be used for every application and have the full range of performance and quality level, including the ability to accurately reproduce colors. This comes from the fact that LEDs are built directly into fixtures, lamps and strips, as in the example image below:

The illuminated ceiling or stretch ceiling is very interesting trend in interior lighting. By using a translucent material many square meters in size with a backlighting system, a diffuse, even and relaxing illumination of interiors can be created. The main advantage of this type of lighting is the absence of glare, as the light sources are distributed over a large area and hidden behind the material.

The backlight source is usually low or medium brightness LEDs (5 to 50 lumens) mounted on strips or modules. Since the illuminated surface has a large area, such low power illumination is the best choice.

Illuminated stretch ceilings can have personalized shapes and even feature translucent images. They can therefore influence the overall design of a room much more than other lighting fixtures. From a lighting design perspective, uniform light should be supplemented by spotlights or lamps that can draw attention to specific areas or objects.

The proper design and installation of a luminous ceiling has a number of unique challenges that we will address in this article.