Abstract: A zoom projection lens with eleven lens elements is provided. The zoom projection lens sequentially includes a first lens group, a second lens group, a third lens group, an aperture stop, a fourth lens group and a fifth lens group along an optical axis from a screen side to an image source side. The first lens group has a negative refractive power and includes three lens elements. The second lens group has a positive refractive power and includes one lens element. The third lens group has a positive refractive power and includes one lens element. The fourth lens group has a negative refractive power and includes four lens elements. The fifth lens group has a positive refractive power and includes two lens elements. A first lens element in the first lens group is an aspheric lens made of plastic.

Abstract: A zoom lens including a movable first lens group and a movable second lens group sequentially arranged along an optical axis from a magnifying side to a reduction side is provided. The first lens group and the second lens group respectively includes at least one lens. The zoom lens meets a condition, and the condition is: a product of a refractive index temperature coefficient and a refractive index temperature coefficient change rate of at least some of the lenses in the first lens group and the second lens group is less than 0. In addition, a manufacturing method of a zoom lens is also provided. The zoom lens and the manufacturing method thereof provided in the invention can achieve favorable and consistent imaging quality in both a high temperature environment and a low temperature environment under different modes.

Abstract: The invention provides a projection zoom lens and a projector. The projection zoom lens includes a first lens group and a second lens group sequentially arranged along an optical axis from a screen end to an image source end. The first lens group has a negative refractive power and includes a first lens, a second lens, and a third lens. The second lens group has a positive refractive power and includes a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, and a twelfth lens. The first lens to the twelfth lens are sequentially arranged along the optical axis from the screen end to the image source end, and the refractive powers of the first lens to the twelfth lens are negative, negative, positive, positive, positive, negative, negative, positive, positive, negative, positive, and positive.

Abstract: A zoom projection lens with eleven lens elements is provided. The zoom projection lens sequentially includes a first lens group, a second lens group, a third lens group, an aperture stop, a fourth lens group and a fifth lens group along an optical axis from a screen side to an image source side. The first lens group has a negative refractive power and includes three lens elements. The second lens group has a positive refractive power and includes one lens element. The third lens group has a positive refractive power and includes one lens element. The fourth lens group has a negative refractive power and includes four lens elements. The fifth lens group has a positive refractive power and includes two lens elements. A first lens element in the first lens group is an aspheric lens made of plastic.