How to choose an industrial camera lens? Detailed explanation of industrial camera lens parameters
The selection process of lenses is a process of step-by-step clarification of the various parameters of industrial lenses.As a kind of imaging device,industrial camera lens is generally matched with the light source.The camera forms a complete image acquisition system,so the selection of industrial camera lens is limited by the requirements of the whole system.In general,it can be analyzed and considered from the following six aspects.
1.the prioritization of matching requirements
according to the actual application characteristics,there may be special requirements that should be clarified first,such as whether there is a measurement function,whether a telecentric lens is required,whether the depth of field is very large,etc.Depth of field is not usually taken seriously,but it must be taken into account in any imaging system.
2.select target area and size
the selection of the optical size of the lens should be based on the optical size of the camera,the optical size of the lens is larger than that of the camera;the optical size of the lens can not make good use of the line of sight of the lens;the image size of the industrial lens should be compatible with the size of the photosensitive surface of the camera and follow the principle of"large is compatible with small"-the photosensitive surface of the camera must not exceed the scale of the image plane marked on the lens-otherwise the image quality of the edge field of view cannot be guaranteed.
3.select the lens type
for general inspection or flat dimensional inspection applications,select a non-telecentric lens;for dimensional inspection,especially non-flat dimensional inspection,you must select a telecentric lens.
4.Depth of field and light environment
Depth of field and light environment are coordinated,the light is sufficient,and a small aperture can be selected in the area directly illuminated by the light source to increase the depth of field and improve the shooting clarity.Places with insufficient light source require a larger aperture or a higher photosensitive chip.
5.Interface and aperture
The aperture of an industrial camera lens mainly affects the brightness of the image surface.The final image brightness is determined by many factors:aperture,camera gain,integration time,light source,etc.The interface of the industrial lens refers to the connection interface with the camera.The two need to match.If they cannot be matched directly,transfer must be considered.C mount or CS mount,the distance of C mount is 17.5mm and the distance of CS mount is 12.5mm.If used,focus cannot be achieved.
6.Wavelength and zoom
The operating wavelength of an industrial camera lens and whether it needs to zoom is relatively simple.During the development process,for applications that require changing and extending the magnification,choose a zoom lens,otherwise you can choose a fixed focus lens.Regarding the operating wavelengths of industrial lenses,the most common ones are visible light bands and other bands.
In the process of industrial camera lens selection,in order to facilitate friends to calculate industrial lens parameters,the optical size table is now provided for your reference.
1.1 inches-optical size:width 12mm*height 12mm,diagonal 17mm
1 inch-optical size:width 12.7mm*height 9.6mm,diagonal 16mm
2/3 inches-optical size:width 8.8mm*height 6.6mm,diagonal 11mm
1/1.8 inches-optical size:width 7.2mm*height 5.4mm,diagonal 9mm
1/2 inch-optical size:width 6.4mm*height 4.8mm,diagonal 8mm
1/3 inch-optical size:width 4.8mm*height 3.6mm,diagonal 6mm
1/4 inch-target size:width 3.2mm*height 2.4mm,diagonal 4mm
On the basis of determining that industrial cameras and lenses are two separate things,talking about the type of choice,if you want to get photos of the object being measured,industrial cameras and lenses are both essential.