1.High intensity discharge (HID) lamp
Although fluorescent bulbs were once the most common type of indoor growth lamp, today's HID lamps are the most popular. High intensity discharge lamp has high lumen/watt efficiency. There are several different types of HID lamps, including mercury vapor, metal halide, high pressure sodium and conversion bulbs. Metal halides and HPS lamps produce a spectrum somewhat similar to that of the sun and can be used to grow plants. Mercury vapor lamps, the first type of HIDs, are widely used for street lighting, but when it comes to indoor gardening, they produce relatively poor spectra for plant growth, so they are mostly replaced by other types of HID for growing plants.
All HID growth lamps require ballasts, each with a specific wattage. Hot HID power includes 150W, 250W, 400W, 600W and 1000W. Among all sizes, the 600W HID lamp has the highest light efficiency, followed by 1000W and 600W HPS which have 7% more light than 1000W HPS.
Although all HID lamps use the same principle, different types of bulbs have different starting and voltage requirements, as well as different working characteristics and physical shapes. Because such a bulb will not work unless a matching ballast is used, even if the bulb is installed. In addition to producing lower levels of light, mismatched bulbs and ballasts can stop working or even burn out immediately.
2.LED (light emitting diode)
LED LED lights consist of light-emitting diodes, usually in a case with a radiator or built-in fan. LED lights usually do not require a separate ballast and can be plugged directly into a standard power outlet for direct use.
LED growth lamps vary according to their use. Green, red, far-red, and blue light spectra are known to have effects on root formation, plant growth, and flowering from studies of light morphogenesis, but there are not enough scientific studies or field tests to recommend specific color ratios for experiments using LED growth lamps. It has been shown that many plants will grow normally if given red and blue light. However, many studies have shown that red and blue light only provide the most cost-effective way to grow, and that plants still grow better when light supplements green.
White LED growth lamps provide a full spectrum, designed to mimic natural light and provide a balanced spectrum of red, blue and green for plants. The spectrum used varies, but white LED growth lamps are designed to emit a similar amount of red and blue light, with increased green light appearing as white. White LED lights are often used as supplementary lighting for home and office Spaces.
A large number of plant species have been evaluated in greenhouse experiments to ensure that they are of higher quality in terms of biomass and biochemical composition, even in line with field conditions. The performance of mint, basil, lentil, lettuce, cabbage, parsley, and carrots was measured by assessing the health and vitality of the plants and their success in promoting growth. Promotes the selection of ornamental plants for mass flowering.
In philips lighting company in LED grow light test, in order to find the best light in greenhouse cultivation of vegetables recipes, they found the following several aspects of light affect plant growth, photosynthesis and plant growth light intensity, light always change over time what time of day, (spectrum), direction, and distribution of light on plants. It's worth noting, however, that in the tests between tomatoes, mini cucumbers and bell peppers, the best recipes for all plants varied, depending on the crop and the region, so they now have to optimize LED lighting and errors in greenhouses based on the experiments. They have shown that LED light affects disease resistance, taste and nutrition levels, but by 2014 they had not found a practical way to use this information.
The diode design used for the initial LED LED is usually between 1/3 and 1 watt. Today, however, LED growth lamps typically use higher-power diodes, such as 3-watt and 5-watt diodes. For highly compact areas, COB chips between 10 and 100 watts can be used. These chips are often less efficient because they dissipate heat.
LED growth lights should keep the plant at least 12 inches (30 cm) away from the plant to prevent burns to the leaves.
Fluorescent lamps have many shape factors, including long, thin bulbs and smaller, more energy efficient ones. The color temperature of fluorescent lamps ranges from 2700K to 10,000K.The luminous efficiency ranges from 30lm/W to 90lm/W.