| 摘要 |
The invention relates to an endoscope and a method for regulating the brightness of an observed field. The endoscope comprises a diaphragm device (66), for controlling the strength of a light flux, from a light source (61) and a light guide (64), to which the light flux may be coupled, in order to illuminate an observed field of an endoscopy. The diaphragm device (66) is connected to a drive (67), which may be controlled in relation to the brightness of the observed field (65). The endoscope further comprises an electro-optical device (70), for creation of an image of the observed field (65) and a computer unit (74), for determination of an illumination parameter, in other words a set-value for the brightness of the observed field (65) and also for regulation of the drive (67), for controlling the diaphragm arrangement (66). The diaphragm arrangement (66) is characterised by comprising a means by which the image of the observed field may be digitised and a luminance image of the observed field generated. Said luminance image is divided into part images and, from each part image, a brightness histogram generated. A weighting matrix with weighting factors for the part images is selected, the histograms for the part images are compared with at least one selected parameter, the weighting factors of the weighting matrix adjusted and normalised, a brightness average value for the histograms calculated for each partial image, the weighting factors and the brightness average value for each partial image multiplied and, for determination of the illumination parameter, the sum for all partial images taken. |
