Abstract: The present invention relates to a zoom (magnification variable) lens optical system that is used for a mobile phone camera or a digital camera. The zoom lens optical system includes, along a light axis in order of arrangement from an object side, a first lens group having a negative refractive power and comprising a prism provided with a reflective surface for bending a light path by reflecting light passed through the first lens at an angle of 90°, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, and a stop, wherein the variation of magnification is performed by moving at least two of the second to fourth lens groups.

Abstract: Embodiments of a zoom lens barrel assembly for an imaging apparatus are provided. The zoom lens barrel has a simple structure and allows efficient space utilization in order to realize a compact size, which is currently required for a mobile imaging apparatus. The zoom lens barrel assembly can stably endure external impacts, provide more precise zoom operations, and stably operate for a long time without a malfunction of a zoom motor, which acts as a drive source. The zoom lens barrel assembly can increase the rotation gain of a driving source and improve space utilization inside a basic skeletal structure of a frame by modifying the structure of a gear train, which cooperatively connects the driving source and a rotary cam member.

Abstract: Embodiments of a zoom lens barrel assembly for an imaging apparatus are provided. The zoom lens barrel has a simple structure and allows efficient space utilization in order to realize a compact size, which is currently required for a mobile imaging apparatus. The zoom lens barrel assembly can stably endure external impacts, provide more precise zoom operations, and stably operate for a long time without a malfunction of a zoom motor, which acts as a drive source. The zoom lens barrel assembly can increase the rotation gain of a driving source and improve space utilization inside a basic skeletal structure of a frame by modifying the structure of a gear train, which cooperatively connects the driving source and a rotary cam member.