1. An optical distance measurement method, comprising: acquiring a plurality of sensed values based on detecting light, wherein the plurality of sensed values include a plurality of rows of sensed values; performing a filtering operation to select a plurality of selected sensed values from the plurality of sensed values, comprising: configuring a threshold value for each row of sensed values, comprising: calculating a maximum of sensed values of a row; calculating a mean of the sensed values of the row; and configuring the threshold value for the row according to an average of the mean and the maximum; comparing sensed values of each row with a corresponding threshold value to select the plurality of selected sensed values; determining a location of a centroid according to the plurality of selected sensed values; and calculating a plurality of depth values with respect to a plurality of detecting points according to the location of the centroid and a plurality of depth information transformation functions respectively corresponding to the detecting points.