Abstract: The present disclosure provides an oral cavity detection method. The method comprises: acquiring an ultraviolet light image of the oral cavity; determining a first region including a tooth region and at least one portion of a gum region based on the ultraviolet light image; acquiring a non-ultraviolet light image of the oral cavity; acquiring from the non-ultraviolet light image a first intermediate image that only includes the corresponding first region of the non-ultraviolet light image, based on the non-ultraviolet light image and the first region; determining a second region that only includes the tooth region, based on the first intermediate image; and determining the proportion of pixels containing dental plaque in a second intermediate image that only includes the corresponding second region of the ultraviolet light image.

Abstract: Provided in the present disclosure is an oral cavity examination method, including: acquiring an oral cavity image; performing median filtering and region segmentation operations on the image to obtain a first intermediate image; converting the first intermediate image from an RGB color space to an HSV color space to obtain a second intermediate image; determining a comparison threshold based on a tooth color; and determining a ratio of pixels within the comparison threshold to pixels of the second intermediate image based on the second intermediate image and the comparison threshold.

Abstract: A voltage converting device includes: a first power supply, having a first positive terminal and a first negative terminal; a first bridge circuit, coupled to the first positive terminal; a second bridge circuit, coupled between the first bridge circuit and the first negative terminal; a second power supply, having a second positive terminal and a second negative terminal; a third bridge circuit, coupled to the second positive terminal; a fourth bridge circuit, coupled between the third bridge circuit and the second negative terminal; and an inductive circuit, coupled between the first bridge circuit and the second bridge circuit.