JP2005085291A - Optical pickup device, optical element used therefor, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize the low back of an optical pickup device especially regarding an optical pickup device, an optical element, and its manufacturing method. <P>SOLUTION: In the optical element 4 constituted of an optical lens 7 and a support 6, adhesives 8 for securing the optical lens to the support are applied not only on an abutment surface between the optical lens 7 and the support 6 but also on the opening end surface side of the support 6 to form a projected part 9, and the height of this projected part 9 is set higher than the upper end surface of the optical lens 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention particularly relates to an optical pickup device corresponding to an information recording medium, an optical element used therefor, and a method for manufacturing the same.

  In general, the optical pickup device 1 includes a light emitting element 2 that generates an optical signal, an optical element 4 that focuses the optical signal on an information recording medium 3, and a light receiving element that receives a reflected signal from the information recording medium 3 as shown in FIG. In recent years, as information terminals such as personal computers have been reduced in height, it is indispensable to reduce the height of the optical pickup device used therefor.

  In such an optical pickup device 1, conventionally, an optical element 4 arranged to face an information recording medium 3 such as a CD or a DVD has an optical lens 7 attached to a cylindrical support 6. The optical lens 7 protrudes from the opening end of the support 6.

As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.
JP-A-10-199027

  However, as the height of the optical pickup device 1 is reduced, the distance between the optical element 4 and the information recording medium 3 is reduced, and the optical lens 7 protruding from the end surface of the support 6 due to rotational shaking of the information recording medium 3 or the like. Is in contact with the information recording medium 3 and damages the optical functional surface of the optical lens 7, so that it is difficult to reduce the distance between the optical lens 7 and the information recording medium 3. Low profile was difficult.

  Therefore, the present invention provides an optical pickup apparatus that can solve such problems and can be reduced in height, an optical element used therefor, and a method for manufacturing the same.

  In order to achieve this object, the invention described in claim 1 of the present invention particularly supports an optical lens and an adhesive for fixing the optical lens to the support in an optical element comprising the optical lens and the support. By providing not only on the contact surface with the body but also on the opening end surface side of the support body to form a protrusion, and setting the height of this protrusion higher than the upper end surface of the optical lens, the end surface of the protrusion is Since it is set higher than the end face of the optical lens, it is possible to prevent the optical lens and the information recording medium from coming into direct contact, and to reduce the height of the optical pickup device.

  According to the second aspect of the invention, in particular, by using an epoxy resin as an adhesive, the protrusion can be easily formed and the surface of the information recording medium can be protected.

  The invention according to claim 3 can prevent the optical lens from dropping off from the support, particularly by providing the projecting portion so as to straddle the upper end surface of the support and the outer peripheral end portion of the optical lens.

  In the invention according to claim 4, in particular, the projecting portion is continuously provided on the entire circumference of the outer peripheral end portion of the optical lens, whereby the hermeticity inside the support can be enhanced.

  In the fifth aspect of the invention, in particular, the upper end surface of the protruding portion is a curved surface, so that even if the information recording medium contacts the protruding portion, the surface can be prevented from being damaged.

  The invention described in claim 6 is composed of an optical lens and a support, and an adhesive for fixing the optical lens to the support is applied to the contact surface of the support with the optical lens, and the optical lens is attached. Then, the adhesive overflows into the opening end surface of the support, and a projection is formed on the opening end surface of the support using the overflowed portion, and the height of the projection is set higher than the upper end surface of the optical lens. Thus, the protruding portion can be easily formed.

  The invention according to claim 7 is a light emitting element for generating an optical signal, an optical element for condensing the optical signal on an information recording medium, and a light receiving element for receiving a reflected signal from the information recording medium. The optical element is formed of an optical lens and a support, and an adhesive for fixing the optical lens to the support is provided on the contact surface between the optical lens and the support as well as the opening end surface of the support By providing a protrusion on the side and setting the height of the protrusion higher than the upper end surface of the optical lens, the height of the optical pickup device can be reduced.

  According to the present invention, in particular, the optical lens and the information recording medium can be prevented from coming into direct contact, and the optical pickup device can be reduced in height.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected and demonstrated about the structure similar to the background art mentioned above.

  FIG. 1 is a diagram showing an optical pickup device 1 for recording / reproducing an optical information recording medium such as a DVD, and its structure is mainly a light emitting element 2 for generating an optical signal, and the optical signal as an information recording medium 3. And an optical element 4 that condenses light, and a beam splitter 10 that branches a reflected signal from the information recording medium 3 to the light receiving element 5.

  The optical element 4 includes an optical lens 7 that optically processes an optical signal, and a support 6 for attaching the optical lens 7 to a housing 1a that forms the optical pickup device 1. As shown in FIG. 2, a step 6a is provided at the opening end of the support 6 having a through-hole so that the diameter on the opening end side is increased, and the outer peripheral portion of the optical lens 7 is placed on the step 6a. The contact surface is fixed with an adhesive 8, and the adhesive 8 is also provided on the opening end surface of the support 6 to form a protruding portion 9. The height of the protruding portion 9 is set above the optical lens 7. Since the end surface of the protrusion 9 is set higher than the end surface of the optical lens 7 by setting it higher than the end surface, the information recording medium 3 is optically coupled to the optical lens 7 even if the information recording medium 3 shown in FIG. The lower end of the protrusion 9 before contacting the functional surface Since the rotating information recording medium 3 can be prevented from coming into direct contact with the optical lens 7, the distance between the information recording medium 3 and the optical element 4 can be reduced, resulting in an optical pickup. The apparatus 1 can be reduced in height.

  The adhesive 8 is selected from a soft and viscous material such as an epoxy resin, so that the protruding portion 9 can be easily raised and the surface of the information recording medium 3 is covered with a hard cover such as polycarbonate. Therefore, even if the information recording medium 3 comes into contact with the protruding portion 9, the surface of the information recording medium 3 can be prevented from being damaged.

  Further, by providing the protruding portion 9 so as to straddle the upper end surface of the support 6 and the outer peripheral end portion of the optical lens 7 as shown in FIG. 2, the adhesive 8 reaches the upper end surface of the support 6 and the optical lens 7. As a result, the adhesive area between the adhesive 8 and the support 6 and the optical lens 7 can be increased and the adhesive force can be improved, and the projecting portion 9 wraps around the upper end surface of the optical lens 7 so that the wraparound portion becomes optical. The lens 7 is mechanically engaged, and the optical lens 7 can be prevented from falling off the support 6.

  Furthermore, although not shown in particular, since the protrusions 9 are continuously provided on the entire circumference of the outer peripheral end portion of the optical lens 7, the airtightness of the contact portion between the optical lens 7 and the support 6 can be improved. When attached to the optical element 4 and the housing 1a as shown in FIG. 1, the internal sealing performance of the optical element 4 can be improved.

  Furthermore, since the upper end surface of the protruding portion 9 is a curved surface, it is possible to prevent the surface of the information recording medium 3 from being damaged even if the information recording medium 3 contacts the protruding portion 9.

  And as the formation method of the protrusion part 9, the adhesive agent 8 is apply | coated to the surface of the level | step difference 6a of the support body 6, and when attaching the optical lens 7, the adhesive agent 8 overflows to the opening end surface of the support body 6, and this What is necessary is just to form with an overflowing part, and it can form easily without using a special method especially.

  In order to protect the surface of the optical element 4 from contact with the information recording medium 3 in this way, a protective sheet may be provided on the surface of the support 6, but the optical lens 7 is attached to the support 6. Attaching a protective sheet to the completed optical element 4 is because the number of work steps increases and the optical functional surface of the optical lens 7 may be soiled by the work. It is possible to more efficiently protect the protrusions according to the present invention described above.

  INDUSTRIAL APPLICABILITY The optical pickup device according to the present invention, the optical element used in the optical pickup device, and the manufacturing method thereof can prevent the optical lens and the information recording medium from being in direct contact with each other, and can reduce the height of the optical pickup device. In particular, it is useful for an optical pickup device corresponding to an information recording medium.

The figure which shows the structure of the optical pick-up apparatus in one embodiment of this invention The figure which shows the optical element used for the optical pick-up apparatus The figure which shows the structure of the conventional optical pick-up apparatus

Explanation of symbols

4 Optical Element 6 Support 7 Optical Lens 8 Adhesive 9 Projection

Claims (7)

An optical lens, a cylindrical support that supports the optical lens at the opening end portion, and an adhesive that fixes the optical lens to the support, and the adhesive between the optical lens and the support. An optical element characterized by being provided not only on the contact surface but also on the opening end surface side of the support to form a protruding portion, and the height of the protruding portion is set higher than the upper end surface of the optical lens. The optical element according to claim 1, wherein an epoxy resin is used as an adhesive. The optical element according to claim 1, wherein the protruding portion is provided so as to straddle the upper end surface of the support and the outer peripheral end portion of the optical lens. The optical element according to claim 3, wherein the protruding portion is provided continuously along the entire circumference of the outer peripheral end portion of the optical lens. The optical element according to claim 1, wherein an upper end surface of the protruding portion is a curved surface. An optical lens, a cylindrical support that supports the optical lens at the opening end portion, and an adhesive that fixes the optical lens to the support, and the adhesive is connected to the optical lens of the support. When the optical lens is attached to the support and applied to the contact surface, the adhesive overflows to the opening end surface of the support, and the protruding portion is formed on the opening end surface side of the support using the overflowed portion. And the height of the protrusion is set higher than the upper end surface of the optical lens. A light emitting element that generates an optical signal, an optical element that focuses the optical signal on an information recording medium, and a light receiving element that receives a reflected signal from the information recording medium, the optical element including an optical lens, A cylindrical support for supporting the optical lens at the opening end portion and an adhesive for fixing the optical lens to the support, and the adhesive is provided on a contact surface between the optical lens and the support. In addition, the optical pickup device is characterized in that a protrusion is formed on the opening end face side of the support, and the height of the protrusion is set higher than the upper end face of the optical lens.

Images