Several major issues to pay attention to when purchasing millions of high-definition lenses

With the popularity of million pixel high-definition cameras in recent years, the demand for corresponding million pixel lenses has also increased. In addition to traditional traffic monitoring, other emerging industry applications such as urban monitoring also prioritize high-definition systems. How can users choose the appropriate lens for themselves when faced with a large number of products from major manufacturers? This article will discuss the characteristics of megapixel lenses, the functions of mainstream megapixel lenses, and how to choose them.

Million pixel lens characteristics

At present, the commonly used million pixel lenses include fixed focus, manual zoom, and electric zoom. There are mature application plans for different industry applications. For example, in the field of traffic capture, a fixed focus million pixel lens is commonly used. So, what is the difference between a million pixel lens and a regular lens?

The difference in clarity

The resolution of the lens is highest at the center of the imaging plane, while the image at the edges is relatively poorer. Ordinary lenses can fundamentally meet the clarity requirements at the center resolution, but the clarity at the edges will decrease significantly. The overall clarity can meet the requirement of 440000 pixels for ordinary cameras.

In practice, there are three key factors that determine the clarity of a lens: 1. Lens material and purity. The less impurities in the lens, the less interference light it produces, and the higher the clarity of the image; 2. Grinding accuracy of lenses. The grinding accuracy of lenses is determined by the grinding equipment, and the difference between domestic lenses and foreign lenses is reflected in this aspect; 3. The coating accuracy of the lens. Accurate control of the coating process is also one of the determining factors for lens clarity.

In addition, the million pixel lens adopts non spherical lenses, which can reduce aberrations and achieve miniaturization design while improving clarity compared to ordinary lenses; Through special optical design technology, the image quality from the center of the image to the surrounding areas is achieved with high resolution and high aspect ratio illumination, which is about 2.5 times better than traditional lenses in terms of resolution. Even in image cropping or zooming functions, high image quality can still be guaranteed.

Spectral transmission is necessary for differentiation

The spectral transmission of the lens also contributes to the improvement of image clarity. The transmission of broadband light will greatly improve the amount of light received by the camera target surface. It can enhance the contrast and brightness of the image, making the details of the image more vivid.

Spectral correction is necessary for differentiation

As long as the transmission of a wide spectrum is sufficient for high-definition imaging, it is still far from enough. If the spectral correction of the lens is lacking, it will result in inaccurate imaging of local wavelengths of light on the camera target surface, leading to the generation of virtual images. This technology cannot be achieved by coating ordinary lenses.

How to choose a million pixel lens

Compared to ordinary lenses, megapixel lenses have incomparable characteristics and advantages, but what issues should we pay attention to when choosing a megapixel lens?

Clarity correspondence

High definition cameras have just entered the market, with clarity often around 1 million pixels, and users often feel that the cost of a million pixel lens is too high. The high-definition camera is equipped with standard definition lenses, and the effect is still good, and the clarity has been greatly improved compared to the standard definition system. But many systems may present blurry images, especially when the center of the image is clear and the edges are blurry. Even if debugging is stopped, satisfactory results cannot be achieved. With the entry of 2-megapixel, 3-megapixel, and 5-megapixel cameras into the market, users are gradually understanding million pixel lenses and starting to rationally choose suitable lenses based on the camera.

Million pixel lenses are classified based on clarity, with common ones being 1.3 million pixels, 2 million pixels, and 3 million pixels. High end products have 5 million pixels, while some excellent manufacturers have achieved 10 million pixels. So when choosing a lens, it is necessary to select a lens product with the same or higher pixels based on the highest resolution of the camera. For example, the commonly used 2-megapixel CCD camera for transportation should be selected based on the practical application environment, with 25mm or 35mm corresponding to 2-megapixel products. The clarity of commonly used electric zoom lenses is generally around 1.3 million pixels, while the demand for telephoto and high-definition lenses is diverse. For high-definition cameras with a resolution of over 2 million, it is recommended to choose a high-definition electric zoom lens that corresponds to its clarity. Therefore, products with a resolution of over 2 million are the first choice. Of course, products with higher clarity should choose lenses with higher pixels, such as those corresponding to 3 million and 5 million pixels.

Select products with corresponding functions based on the camera application

In some projects, cameras require infrared fill lights during use, so lenses with IR function should be used. This way, brighter images can be obtained at night and the problem of night blur can be reduced. For more demanding environments, such as using laser lights to monitor distant targets, it is necessary to ensure that non visible light wavelengths can still achieve a transmittance of over 60% at 900um.

Apply autofocus function lens to handle delay issues

At present, most high-definition cameras on the market use IP output, which means encoding is completed inside the camera. After network transmission, decoding is required in the monitoring center before it can be displayed on the screen. As we all know, cameras cause delays during the encoding process. Similarly, network transmission also causes delays, and the decoding process in the monitoring center also creates delays. Therefore, the more devices passed through and the more times forwarded, the longer the delay will be. These delays combined will seriously affect the operation of monitoring personnel. Regarding products with fixed focus, this local delay has a relatively small impact. As for the system using electric zoom lenses, it brings difficulties in application. On the one hand, it is a high-definition system, and on the other hand, due to the delay superposition mentioned above, the image will always be unfocused or the focusing time will be too long, making it difficult to quickly capture the target. In this situation, it is necessary to choose products with automatic focusing function. By using an automatic focusing lens, the focusing process is automatically completed at the front end, ensuring that the image transmitted back to the center is always clear. This can bring the following benefits to the high-definition system: 1. Reduce the operator's focusing operation on the lens, and extend the service life of the motor; 2. Due to the clear image, the camera can have higher efficiency and compression ratio during encoding, reducing the resource consumption of transmission and storage; 3. Shortened the target capture time, allowing monitoring personnel to read more images per unit time, thereby improving the effectiveness of the monitoring system.

With the improvement of high-definition cameras, more and more systems require the integration of high-definition lenses. Major lens manufacturers have launched high-definition products with different focal lengths, providing users with more choices. With the application of ED lenses, autofocus and other functions in high-definition lenses, the difference between high-definition electric zoom lenses and standard definition products is becoming smaller and smaller. The future trend will be a great integration of products, with high-definition products gradually replacing existing standard definition products and becoming the mainstream of the market.