| 摘要 |
PURPOSE:To obtain the titled lens having a reduced step and an improved productivity without injuring a shading effect by forming the shading parts at an inner side or on a surface of the plastic lens integrally at the same time. CONSTITUTION:The inner diameter D3 is equal to an effective diameter of the plastic lens formed by uniting the shading parts 5 with one body. The notched parts 5a is provided with the titled lens in order to prevent the disorder of the flow of a resin which is injected in forming the titled lens. The shading parts 5 is composed of aluminum which follows in the temp. of a mold and reduces irregularity of the temp. distribution, without having bad effects upon the forming accuracy, and has the high heat conductivity. The shading parts made of aluminium is effected a black alumite treatment to improve the shading effect. The notched parts 5a accords with a gate 8 and then the shading parts 5 is inserted in a holding parts 18. The mold is moved to form a cavity 9 followed by injecting the resin into the cavity to obtain the plastic lens 1 including the shading parts 5 therein.
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