| dc.description.abstract | A 3× zoom lens design for a copy machine is presented. The purpose of the
design is to make copies respectively with the paper size A3、B4 and A4. Selecting
the F/# of Zoom1 to Zoom3 are F/4.2183、F/4.4936、F/4.7692 . Using the
spectrum F-line, d-line, C-line, and d-line is for the reference wavelength.
The total track of this 3× zoom system is fixed, which means the distance of
paper to the sensor is fixed. Given the paper width A3, B4, A4 which are 297 mm,
250 mm, 210 mm. Selecting Toshiba linear CCD for the image sensor and the
effective length is 35.015 mm. Obtaining the result of magnifications about
Zoom1 to Zoom3 are m1= -0.11789, m2= -0.14005 ,m3= -0.16673. Given the size
of the image sensor is 4.7 m, then the resolution of A3, B4, A4 are 637 dpi, 756
dpi, 901 dpi.
The 3× zoom lens design consists of three spherical and five aspherical
lenses. For the Zoom1’s quality of imaging , the value of the MTF 58.4 % at 80
lp/mm with a value of |TMTF-SMTF| 5.3 %. The optical distortion 1.95 %
and the lateral chromatic aberration 1.769 μm. The relative illumination
89.13 %. For the Zoom2’s quality of imaging , the value of the MTF 57.5 % at
80 lp/mm with a value of |TMTF-SMTF| 3.8 %. The optical distortion 1.65 %
and the lateral chromatic aberration 1.020μm. The relative illumination
91.72%. For the Zoom3’s quality of imaging , the value of the MTF 57.9 % at
80 lp/mm with a value of |TMTF-SMTF| 6.5 %. The optical distortion 1.17%
and the lateral chromatic aberration 1.330μm. The relative illumination 89.69
%. | en_US |