This 50m distance measuring meter is made of two parts: the laser distance outside unit and the sole part laser measure module. Great distance range is from 3cm to 50 meters with ±1.5mm high accuracy. Digital distance measuring device is quick and reliable measure with one hand pushing the button. It is designed for hand helding, very convenient to put in your jacket pocket or trouser pocket. 50M Laser Distance Measurer,Mini Laser Measurer, Laser Measure 50M,50M Laser Distance Meter Chengdu JRT Meter Technology Co., Ltd , https://www.jrt-measure.com
1>. Easy to Use. It is very easy to learn how to use a Laser Distance Meter, it can measure distance with pressing a single button.
2>. Safety. Using a laser distance meter to measure is much safer than using a measure tape, for users do not need to climb up and down.
How to improve greenhouse vegetable lighting?
Light conditions inside plastic greenhouses play a crucial role in the growth, yield, and quality of vegetables. During winter and spring, shorter daylight hours and reduced sunlight intensity, combined with frequent cloudy, snowy, rainy, or foggy weather, significantly impact plant development. To counter these challenges, it is essential to implement effective strategies to optimize lighting conditions, which are vital for successful greenhouse vegetable production.
The design and construction of the greenhouse itself have a major influence on light availability. Greenhouses should be located in sunny, leeward areas, ideally facing south (or southeast) to maximize sunlight exposure during the colder months. Improving the structure by using fewer support poles and arches, and replacing them with durable materials that cause less shading, can help increase light penetration. Painting walls and structures with white materials enhances light reflection, while using non-drip films improves light transmission and helps boost both yield and quality.
Proper placement of different vegetable varieties within the greenhouse is also important. Vegetables should be arranged according to their height, following the principle of "low in the north and high in the south," to minimize shading between plants and ensure even light distribution.
In addition to structural adjustments, regular maintenance is necessary. Cleaning the interior and exterior of the plastic film, especially after snowfall, helps maintain optimal light levels. Care must be taken not to damage the film during cleaning. When temperatures allow, covering the greenhouse with insulating materials like straw mats can extend the duration of available light. Covering the entire greenhouse with plastic film can enhance scattered light near the ground, improving overall lighting conditions.
On the north side of the greenhouse, where light is typically limited, installing aluminum reflective screens or hanging silver reflective films can increase light levels by 20 to 40%. In cases of prolonged overcast or foggy weather, artificial lighting such as incandescent, fluorescent, or high-pressure mercury lamps can be used to supplement natural light. Typically, 4 to 5 hours of artificial lighting per day is sufficient. Finally, pruning old, diseased, or excessive leaves and branches helps improve air circulation and increases light access to the lower parts of the plants. These measures collectively contribute to healthier and more productive greenhouse crops.