Video camera unit having an airtight mounting arrangement for an image sensor chip

• US 5,400,072 A
• Filed: 02/16/1990
• Issued: 03/21/1995
• Est. Priority Date: 12/23/1988
• Status: Expired due to Term

• Current Assignee: Renesas Electronics Corporation, Echo Incorporated (Yamabiko Corporation)
• Original Assignee: Hitachi, Ltd., Echo Incorporated (Yamabiko Corporation)
• Inventors: Kodowaki, Masahiko, Niwa, Kunio, Takahashi, Masayuki, Yokoyama, Masaaki, Kojima, Hiroyoshi, Takemoto, Iwao, Iguchi, Atsumu, Izumi, Akiya, Nakajima, Junichirou, Sokei, Hiroichi, Naito, Takamasa
• Primary Examiner(s): Razavi, Michael T.
• Assistant Examiner(s): Ho, Tuan V.
• Application Number:
  US07/480,979
• Time in Patent Office: 1,859 Days
• Field of Search: 358/209, 358/213.11, 358/225, 358/229
• US Class Current: 348/335
• CPC Class Codes: G02B 7/021 for more than one lens
• CPC Class Codes: G02B 9/12 having three components only
• CPC Class Codes: G02B 9/34 having four components only
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils

Abstract

A video camera unit is separated into a holder for receiving lenses and a base on which a solid-state image pickup chip is mounted. The holder and the base are assembled together with the distance between them made variable so that it is possible to adjust the back focus of the lens. Further, a video camera unit has a holder which is separated into a first holder for receiving lenses and a second holder for receiving a solid-state image pickup device so that both holders can be assembled together with the distance between them made variable. Therefore, it is also possible to adjust the back focus of the lens.

Claims

1. A video camera unit comprising:

a plastic lens unit;

a cylindrical holder in which said plastic lens unit is housed, said cylindrical holder having a front end and a back end;

a cylindrical base member including a circular plate having a peripheral edge, and including a cylindrical upright member extending to a predetermined height from the peripheral edge of said circular plate to be integral therewith, said back end of said cylindrical holder being received by said cylindrical base member;

a solid-state image sensor chip mounted on said plate for receiving light having passed through said plastic lens unit, said height of said cylindrical upright member being such that at least part of said cylindrical upright member adjustably surrounds said back end of said cylindrical holder for focusing adjustment between said plastic lens unit and said solid-state image sensor on said circular plate when said back end of said cylindrical holder is received by said cylindrical base member;

a cylindrical case having front and back end openings opposed to each other and surrounding said cylindrical holder and said cylindrical upright member of said cylindrical base member, said cylindrical upright member of said cylindrical base member being coupled to said cylindrical case in an airtight structure; and

a transparent cap mounted on said cylindrical case in an airtight structure to cover said front end opening of said cylindrical case, said back end opening of said cylindrical case being covered with said circular plate of said cylindrical base member, and said lens unit in said cylindrical holder receiving light coming from through said transparent cap, wherein said cylindrical case, said cylindrical base member and said transparent cap cooperate with one another to provide an airtight sealed structure for said plastic lens unit and said solid-state sensor chip.

2. A video camera unit according to claim 1, wherein said cylindrical upright member has an inner diameter substantially equal to an outer diameter of said back end of said cylindrical holder.

3. A video camera unit according to claim 1, wherein an end of said upright member of said cylindrical base member and that portion of said case which contacts said end of said upright member are formed tapered, respectively.

4. A video camera unit according to claim 1, wherein an end of said upright member of said cylindrical base member is tapered to provide a chamfered portion and has a concave groove for application of a bonding agent.

5. A video camera unit according to claim 1, wherein said cylindrical base member is formed with grooves for carrying jigs in an outer peripheral portion thereof.

6. A video camera unit according to claim 1, wherein bonding and fixing of said cylindrical case and said cylindrical base member to each other is maintained by at least one press-fitting projection provided on an outer peripheral surface of said base member into said case.

7. A video camera unit according to claim 1, wherein said lens unit includes first and second lenses, wherein said second lens is interposed between said first lens and said sensor chip, and wherein, assuming that a diameter of said first lens is d1 and a diameter of said second lens is d2, the following formula is satisfied:

8. A video camera unit according to claim 1, wherein said transparent cap is spaced apart from said plastic lens unit.

9. A video camera unit according to claim 1, wherein said cylindrical base member is a one-piece unit.

12. A video camera unit according to claim 1, wherein said solid-state image sensor chip is a bare chip.

10. A solid-state image pickup device comprising:

a base;

a solid-state image sensor mounted on said base;

a cylindrical holder having an inner wall, a front end and a back end, said back end being coupled to said base;

a plurality of plastic lenses housed in said cylindrical holder, each of said lenses having a central portion for focusing light and also being provided at its peripheral edge with a rib in contact with the inner wall of said cylindrical holder, wherein, for each of said lenses, the thickness of its rib is greater than the thickness of at least a part of said central portion of the lens, and wherein a surface of each of said ribs which contacts said inner wall of said cylindrical holder is tapered for facilitating insertion of said lenses into said holder for said housing of said lenses;

a lens holding cover provided at said front end of said cylindrical holder for fixing said plurality of plastic lenses; and

light shielding plates provided between adjacent ones of said plurality of plastic lenses,

wherein said light shielding plates are located between ribs of adjacent lenses, and wherein the thicknesses of said ribs and the thicknesses of said light shielding plates serve to define distances between the central portions of said lenses.

11. A solid-state image pickup device according to claim 10, wherein at least one of said plastic lenses is an aspherical lens.

13. A solid-state image pickup device according to claim 10, wherein said solid-state image sensor is a bare chip.

14. An airtight sealed video camera unit using a bare solid-state image sensor chip comprising:

a plastic lens unit;

a cylindrical holder in which said plastic lens unit is housed, said cylindrical holder having a front end and a back end;

a one-piece cylindrical base member including a circular plate having a peripheral edge, and including a cylindrical upright member extending to a predetermined height from the peripheral edge of said circular plate to be integral therewith, said back end of said cylindrical holder being received by said cylindrical base member;

a bare solid-state image sensor chip mounted on said plate for receiving light having passed through said plastic lens unit, said height of said cylindrical upright member being such that at least part of said cylindrical upright member adjustably surrounds said back end of said cylindrical holder for focusing adjustment between said plastic lens unit and said bare solid-state image sensor on said circular plate when said back end of said cylindrical holder is received by said cylindrical base member;

a cylindrical case having front and back end openings opposed to each other and surrounding said cylindrical holder and said cylindrical upright member of said cylindrical base member, said cylindrical upright member of said cylindrical base member being coupled to said cylindrical case in an airtight structure; and

a transparent cap mounted on said cylindrical case in an airtight structure to cover said front end opening of said cylindrical case and to be spaced apart from said plastic lens unit, said back end opening of said cylindrical case being covered with said circular plate of said cylindrical base member, and said lens unit in said cylindrical holder receiving light coming from through said transparent cap;

wherein said cylindrical case, said cylindrical base member and said transparent cap cooperate with one another to provide a airtight sealed structure for said plastic lens unit and said solid-state image sensor chip.

15. An airtight sealed video camera unit according to claim 14, wherein said cylindrical upright member has an inner diameter substantially equal to an outer diameter of said back end of said cylindrical holder.

16. An airtight sealed video camera unit according to claim 14, wherein an end of said upright member of said cylindrical base member and that portion of said case which contacts said end of said upright member are formed tapered, respectively.

17. An airtight sealed video camera unit according to claim 14, wherein an end of said upright member of said cylindrical base member is tapered to provide a chamfered portion and has a concave groove for application of a bonding agent.

18. An airtight sealed video camera unit according to claim 14, wherein said cylindrical base member is formed with grooves for carrying jigs in an outer peripheral portion thereof.

19. An airtight sealed video camera unit according to claim 14, wherein bonding and fixing of said cylindrical case and said cylindrical base member to each other is maintained by at least one press-fitting projection provided on an outer peripheral surface of said base member into said case.

20. An airtight sealed video camera unit according to claim 14, wherein said lens unit includes first and second lenses, wherein said second lens is interposed between said first lens and said sensor chip, and wherein, assuming that a diameter of said first lens is d1 and a diameter of said second lens is d2, the following formula is satisfied:

space="preserve" listing-type="equation">d1>

d2.