A range in relation to an optical system, such as a camera lens, representing distances great enough that light rays reflected from objects within the range may be regarded as parallel. (聚焦區)無(wú)限遠與光學(xué)系統(如照像鏡頭)有關(guān)的一個(gè)范圍，表示距離是如此之遠，以至于從在這一距離的物體上反射回來(lái)的光可以視為平行光線(xiàn)
The camera lens must be screened from direct sunlight. 照相機的鏡頭不可受到陽(yáng)光的直射。
