The photo above is an image taken by a dashcam.Ghosts and flares like this can sometimes be seen in images taken by dashcams.If ghosts and flares like this appear in the images taken by onboard cameras of self-driving cars, they can delay the detection and recognition of obstacles and lead to an accident.
What are ghosts and flares?
According to a specialized website, a ghost is “a light image that occurs when strong light enters the lens, such as when the lens is facing the light source, and as a result of which the light reflected within the lens appears in the shape of an aperture or an ellipse.”
A flare is a phenomenon in which light is reflected within the lens or camera body, causing an inaccurate color reproduction or uneven brightness in the image.
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Camera manufacturers, lens manufacturers, and even smartphone manufacturers are all putting effort into producing cameras and lenses that are less prone to suffer from ghosts and flares.Improving the quality of images is directly linked to the performance of the camera. It also leads to more accuracy in the way we utilize images and video footage.
That is the reason behind our creation of the XL-500V1 Fiber Light Source Device for Ghost Evaluation, a light source device that can reproduce ghosts and flares in the same way as when directly photographing the sun.
It uses a 500 W xenon lamp, and its light spectrum is corrected with a filter and focused into a fiber so that the 15 mm diameter lens at the tip of the fiber is made to look like a simulated sun.In other words, it is a light source device that allows you to get, by directly photographing the lens at the tip of the fiber, the same ghosts and flares as when photographing the sun.The two photos below are taken by the same camera: one in natural sunlight and the other using the XL-500V1. You can see that a similar ghost appears in the same position.
The diameter of the lens attached to the tip of the fiber is designed to appear in the same size as the sun, and this allows the device to reproduce a similar ghost in the same location.
Ghosts and flares are caused by, among other factors, unexpected reflections from the sides due to the thickness of the lens or reflections within the lens holder.Of course, the quality of polishing of the surface and the purity of the glass part are also important factors. In particular, the evaluation of ghost and flare for cameras used in autonomous driving is becoming increasingly important.
If you want to come up with solutions against ghosts and flares of camera lenses while still indoors, SERIC has an abundance of experience that can help you.