Injection molded plastic lens for relay lens system and optical imaging probe

  • Moonwoo La
  • Sang Min Park
  • Wonkyoung Kim
  • Changho Lee
  • Chulhong Kim
  • Dong Sung Kim


In this study, we designed, fabricated and characterized a plastic lens which can be used as an optical compartment of a relay lens system for a disposable endoscope or an imaging probe for optical-resolution photoacoustic microscopy (OR-PAM). Cost-effective injection molding using polycarbonate (PC) as a material was conducted for the mass production of the PC lens. The effects of important processing parameters, i.e. mold temperature, injection speed, packing pressure and packing time, on the transcription quality of the PC lenses were investigated quantitatively using the design of experiments based on the Taguchi method. Optical performances, i.e., focal length and birefringence, were evaluated to determine the optimal injection molding condition for the replication. The PC lenses facilitated the feasibility of developing a disposable length-adjustable endoscope comprising a relay lens system. The PC lens was also applied to an optical imaging probe in an OR-PAM for in vivo observation of mouse micro-vasculatures.


Plastic lens Injection molding Taguchi method Afocal relay lens system Disposable endoscope Photoacoustic microscopy 


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Copyright information

© Korean Society for Precision Engineering and Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Moonwoo La
    • 1
    • 4
  • Sang Min Park
    • 1
  • Wonkyoung Kim
    • 1
  • Changho Lee
    • 2
  • Chulhong Kim
    • 3
  • Dong Sung Kim
    • 1
  1. 1.Department of Mechanical EngineeringPohang University of Science and TechnologyGyeongsangbuk-doSouth Korea
  2. 2.Future IT Innovation LaboratoryPohang University of Science and TechnologyGyeongsangbuk-doSouth Korea
  3. 3.Department of Creative IT EngineeringPohang University of Science and TechnologyGyeongsangbuk-doSouth Korea
  4. 4.Molds & Dies R&D GroupKorea Institute of Industrial TechnologyIncheonSouth Korea

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