F


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z     1 2 3 4 5 6 7 8 9..........................................

 FFC   Flat Field Correction: a CCD imager is composed of a two dimensional array of light sensitive detectors or pixels. The CCD array is mechanically quite stable with the pixels retaining a rigidly fixed geometric relationship. Each pixel within the array, however, has its own unique light sensitivity characteristics. As these characteristics affect camera performance, they must be removed through calibration. The process by which a CCD camera is calibrated is known as "Flat Fielding" or "Shading Correction".
 F-Stop / F#  The f/number is an indication of the brightness of the lens. It is the measurement of the ratio between the focal length and the diameter of the entrance pupil (where the light enters the lens). The f/number is directly proportional to the focal length and inversely proportional to the effective diameter of the lens. It determines the amount of light reaching the camera sensor. The smaller the value, the larger the opening and the brighter the image produced by the lens.
 FFT Attenuate  Attenuates the frequencies of a complex image.
 FFT Filter  Applies a frequency filter to the image. This function performs three steps. First, it finds the fast Fourier transform (FFT) of the source image, which is a complex image. Then the function filters (truncates or attenuates) the complex image.
 FFT High Pass
  Removes low frequencies.
 FFT Low Pass
  Removes high frequencies.
 FFT Mode
  Determines which frequencies to truncate or attenuate.
 FFT Truncate
  Truncates the frequencies of a complex image.
 FFT Truncation Frequency %  Percentage of the frequencies retained within a Fourier-transformed image. This percentage is expressed with respect to the length of the diagonal of the FFT image and the Mode value.
 Field of View
  Field of view (FOV) is the area covered by the lens' angle of view.
 Filter Size  Sets the size of the filter for the Lowpass and Median functions. Typical made up of kernels.
 Filters  Prepares an image for processing so you can extract only the information you need from the image. Most of these filters apply a kernel across the image.
 FireWire  FireWire (also known as i.Link or IEEE 1394) is a personal computer (and digital audio/video) serial bus interface standard, offering high-speed communications. It is often used as an interface for industrial cameras.
 Fixed Focal Length Lens  Non-zoomed lenses where the distance between the sensor and center of the lens is fixed
 Fixed pattern noise  abbr. FPN. If the output of an image sensor under no illumination is viewed at high gain a distinct non-uniform pattern, or fixed pattern noise, can be seen. This fixed pattern can be removed from the video by subtracting the dark value of each pixel from the pixel values read out in all subsequent frames. Dark fixed pattern noise is usually caused by variations in dark current across an imager, but can also be caused by input clocking signals abruptly starting or stopping or if the CCD clocks do not closely match one another. Mismatched CCD clocks can result in high instantaneous substrate currents, which, when combined with the fact that the silicon substrate has some non-zero resistance, can cause in the substrate potential bouncing. The pattern noise can also be seen when the imager is under uniform illumination. An imager which exhibits a fixed pattern noise under uniform illumination and shows no pattern in the dark is said to have light pattern noise or photosensitivity pattern noise. In addition to the reasons mentioned above, light pattern noise can be caused by the imager becoming saturated, the non-uniform clipping effect of the anti-blooming circuit, and by non-uniform, photosensitive pixel areas often caused by debris covering portions of some pixels.
 Flat Field Correction
  Flat Field Correction: (abbr. FFC) a CCD imager is composed of a two dimensional array of light sensitive detectors or pixels. The CCD array is mechanically quite stable with the pixels retaining a rigidly fixed geometric relationship. Each pixel within the array, however, has its own unique light sensitivity characteristics. As these characteristics affect camera performance, they must be removed through calibration. The process by which a CCD camera is calibrated is known as "Flat Fielding" or "Shading Correction".
 Focal Length
  Focal length is the distance between the camera sensor and the center of the lens. The greater the focal length, the larger the image will appear. Therefore, the greater the focal length, the more the lens becomes telephoto in application.
 FOV  FOV = field of view. See field of view
 FPGA   Field Programmable Gate Array: a specially made digital semiconductor. With an FPGA, a design engineer is able to program electrical connections on site for a specific application.
 FPN  FPN = fixed pattern noise. Related with the dark current is its electrical behavior to be regionally different on the sensor. This introduces a structural spatial noise component, called fixed pattern noise, although it’s not meant temporal, visible with low illumination conditions. FPN is typically more dominant with CMOS sensors than with CCD, where it can be ignored mostly. This noise nfpn [%] is usually quantified in % of the mean dark level.
 Frame  An individual picture image taken by a digital camera. Using an interlaced camera, a frame consists of 2 interlaces fields.
 Frame Grabber
  A device that interfaces with a camera and, on command, samples the video, converts the sample to a digital value (if the framegrabber is analog instead of digital) and stores that in a computer's memory. In contrast to Vision Processor boards, which have complex image processing capabilities (usually more than two functions), Frame grabbers have simple image processing capabilities (usually two or less functions).
 Frame Rate
  Frame rate is the measure of camera speed. The unit of this measurement is frames per second (fps) and is the number of images a camera can capture in a second of time. Using area of interest (AOI) readout, the rate can be increased.
  Front Illumination 
  Full Binning
  If horizontal and vertical binning are combined, every 4 pixels are consolidated into a single pixel. At first, two horizontal pixels are put together and then combined vertically. This increases light sensitivity by a total of a factor of 4 and at the same time signal-to-noise separation is improved by about 6 dB. Resolution is reduced, depending on the model. See also: horizontal binning and vertical binning




An innovative leader in machine vision and laser integration deploying systems using advanced sensor technologies servicing industrial automation, scientific and military partners.