在計算機視覺中，二維計算機坐標和三維物體空間坐標的關系可通過攝像機模型來
建立。模型中的參數包括：攝像機幾何、光學特性參數（內參數）及攝像機空間位置參數（外參數）。攝像機的標定就是要確定這些參數。本文分析了三維空間點投影在像平面的像點產生畸變的原因：在大視場攝像機鏡頭各向同性，而且物像空間媒質均勻的情況下，像素單位元面積產生的變化引起像點畸變，并在實際圖像坐標到計算機圖像（幀存）坐標標定過程中推導出CCD 傳感器單元x 方向的比例系數x N 的表達式，并進行了實驗測量分析，取得的結果對提高標定精度具有意義。
關鍵詞： 計算機視覺，三維重建，攝像機模型，攝像機標定，畸變
Abstract: With computer visual technology, the relationship between 2-dimensional computer
coordinate and 3-dimensional space coordinate system is built by camera model. Model
parameters include camera geometrical and optical (inside parameters) and space camera
positional parameters (outer parameters). Camera calibration aims at getting these. The paper
produces that the essence of distortion produced by image spot on the image plane projected from 3-dimensional space dot is due to distortion of pixel unit area. And deduce expression of scale coefficient x N along axe x of CCD sensor unit during calibration from physical image coordinate system to computer frame system.
Key words: Computer visual，3-dimensional reconstruction，camera model，camera
calibration，distortion