Image sensor module with light-shielding diaphragm made of ink, and method of making the same

• US 7,391,457 B2
• Filed: 04/24/2002
• Issued: 06/24/2008
• Est. Priority Date: 04/24/2001
• Status: Expired due to Fees

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Onishi, Hiroaki, Fujimoto, Hisayoshi
• Primary Examiner(s): Ye; Lin
• Assistant Examiner(s): Jerabek; Kelly L
• Application Number:
  US10/128,250
• Publication Number:
  US 20020154239A1
• Time in Patent Office: 2,253 Days
• Field of Search: 348/340, 348/335, 348373-375, 359/819, 359/601, 359/738, 359/894, 359/740, 257431-435, 382/104, 438/51
• US Class Current: 348/340
• CPC Class Codes: G02B 7/022 lens and mount having complementary engagement means, e.g. screw/thread
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices

Abstract

An image sensor module includes a lens member, a resin frame that holds the lens member, a diaphragm formed on the lens member, an image sensor chip that receives light converged by the lens member, and a supporting board upon which the image sensor chip is mounted. The board is fixed to the bottom side of the resin frame. The diaphragm includes an opening for allowing the passage of light, and a light-shielding portion which is entirely held in contact with the lens member. The lens member is glued to the frame so that any additional fixing element such as a lens cap is unnecessary.

Claims

1. An image sensor module comprising:

a lens member including a first surface and a second surface opposite to the first surface;

a frame that holds the lens member, the frame including a loop-shaped top surface and a base surface opposite to the top surface, the frame being internally provided with a lens holding space for accommodating the lens member in a manner such that the lens member avoids protruding beyond the top surface of the frame;

a diaphragm formed on the first surface of the lens member, the diaphragm including an opening and a light-shielding portion;

an image sensor chip that receives light converged by the lens member; and

a board upon which the image sensor chip is mounted, the board being fixed to the base surface of the frame;

wherein the first surface of the lens member includes a flat torus portion and a concave portion surrounded by the torus portion, the concave portion corresponding in position to the opening of the diaphragm, the concave portion projecting toward the second surface of the lens member from the torus portion,

wherein the diaphragm is made of light-shielding ink, the light-shielding portion of the diaphragm being entirely held in direct contact with the flat torus portion of the lens member, the diaphragm being substantially flush with the top surface of the frame.

2. The module according to claim 1, wherein an inner diameter of the lens holding space is smaller than an outer diameter of the lens member.

3. The module according to claim 1, wherein the second surface of the lens member is provided with a convex light-emitting portion.

4. The module according to claim 3, wherein the lens member includes a cylindrical wall surrounding the convex light-emitting portion.

5. The module according to claim 4, wherein the cylindrical wall includes a flat reference contact surface for positioning the lens member relative to the frame, and wherein the convex light-emitting portion avoids protruding beyond the reference contact surface.

6. The module according to claim 5, wherein the reference contact surface is perpendicular to an optical axis of the lens member.

7. The module according to claim 1, further comprising a bonding layer for fixing the lens member to the frame.

8. The module according to claim 1, further comprising an optical filter disposed between the lens member and the image sensor chip.

9. The module according to claim 8, wherein the frame is internally provided with a chip accommodating space that accommodates the image sensor chip, the chip accommodating space being hermetically closed by the board and the optical filter.

10. A method of making an image sensor module, the method comprising the steps of:

mounting an image sensor chip onto a supporting board;

preparing a lens holding frame including a loop-shaped top surface and a base surface opposite to the top surface, the frame being internally provided with a lens holding space;

forming an intermediate assembly by fixing the board to the base surface of the lens holding frame;

fixing the intermediate assembly to an external element by reflow soldering; and

fixing a lens member to the lens holding frame in a manner such that the lens member is accommodated in the lens holding space without protruding beyond the top surface of the frame, the lens member including a first surface and a second surface opposite to the first surface;

wherein the first surface of the lens member is formed with a diagram diaphragm including an opening and a light-shielding portion,

wherein the first surface of the lens member includes a flat torus portion and a concave portion surrounded by the torus portion, the concave portion corresponding in position to the opening of the diaphragm, the concave portion projecting toward the second surface of the lens from the torus portion,

wherein the diaphragm is made of light-shielding ink, the light-shielding portion of the diaphragm being entirely held in direct contact with the flat torus portion of the lens member, the diaphragm being substantially flush with the top surface of the frame.

11. The method according to claim 10, wherein the fixing of the lens member is performed by using a glue.

12. The method according to claim 10, wherein the fixing of the lens member is performed by press-fitting the lens member into the lens holding frame.