Abstract
Provided are an optical distance measuring apparatus, which is capable of accurately measuring a distance, whatever the temperature may be, and which can be easily manufactured at low cost, and an electronic apparatus mounted with the optical distance measuring apparatus. A lead frame of the optical measuring apparatus has two or more first reinforcing terminals, each of which has a part extending in a direction substantially orthogonal to a direction in which a connecting part between a light emitting header and a light receiving header extends. The first reinforcing terminals are fixed by a first light blocking resin body and connected to the light receiving header.
Claims
1. An optical distance measuring apparatus comprising: a lead frame having, on a same plane, a light emitting header, a light receiving header, and a connecting part extending in one direction to connect the light emitting header with the light receiving header; a light emitting element mounted on the light emitting header; a light receiving element mounted on the light receiving header and configured to detect a spot position of light emitted from the light emitting element and then reflected by an object to be measured; a light permeable resin body sealing the light emitting element and the light receiving element; a first light blocking resin body sealing the light permeable resin body in an integral manner, the first light blocking resin body including a light blocking wall that is positioned between the light emitting element and the light receiving element; a light emitting lens having light permeability, the light emitting lens mounted to the first light blocking resin body so as to be positioned above the light emitting element; and a light receiving lens having light permeability, the light receiving lens mounted to the first light blocking resin body so as to be positioned above the light receiving element, the lead frame having at least two first terminals which are connected to the light receiving header and extend in a direction substantially orthogonal to a direction in which the connecting part extends, and each of the first terminals being fixed by the first light blocking resin body.
2. The optical distance measuring apparatus according to claim 1, wherein each first terminal is provided near the light blocking wall.
3. The optical distance measuring apparatus according to claim 1, wherein each first terminal has a portion that underlaps the light blocking wall in a direction substantially orthogonal to the direction in which the connecting part extends.
4. The optical distance measuring apparatus according to claim 1, wherein the lead frame has at least two second terminals which are connected to the light emitting header and extend in a direction substantially orthogonal to the direction in which the connecting part extends, and wherein each of the second terminals is fixed by the first light blocking resin body.
5. The optical distance measuring apparatus according to claim 1, wherein the lead frame has a third terminal which is connected to the light receiving header and which extends, on one side of the light receiving header opposite from the light emitting header, substantially in the direction in which the connecting part extends, and wherein the third terminal is fixed by the first light blocking resin body.
6. The optical distance measuring apparatus according to claim 1, wherein the lead frame has a fourth terminal which is connected to the light emitting header and which extends, on one side of the light emitting header opposite from the light receiving header, substantially in the direction in which the connecting part extends, and wherein the fourth terminal is fixed by the first light blocking resin body.
7. An electronic apparatus comprising the optical distance measuring apparatus according to claim 1.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1A is a transparent view of a primary molded body which is obtained after a primary molding step in the production process of an optical distance measuring apparatus of a first embodiment of the present invention;
(2) FIG. 1B is a top view of a structure of the optical distance measuring apparatus in process of production after a secondary molding step following the step of FIG. 1A;
(3) FIG. 1C is a transparent view of FIG. 1B;
(4) FIG. 2A is a sectional view taken along line A-A of FIG. 1C;
(5) FIG. 2B is a sectional view taken along line B-B of FIG. 1C;
(6) FIG. 3A is a transparent view of a structure obtained after a primary molding step in the production process of an optical distance measuring apparatus of a second embodiment of the present invention;
(7) FIG. 3B is a top view of a structure of the optical distance measuring apparatus in process of production after a secondary molding step following the step of FIG. 3A;
(8) FIG. 3C is a transparent view of the structure of FIG. 3B;
(9) FIG. 4A is a transparent view of a structure obtained after a primary molding step in the production process of an optical distance measuring apparatus of a third embodiment of the present invention;
(10) FIG. 4B is a top view of a structure of the optical distance measuring apparatus in process of production after a secondary molding step following the step of FIG. 4A;
(11) FIG. 4C is a transparent view of the structure of FIG. 4B;
(12) FIG. 5 is a sectional view taken along line B-B of FIG. 4C;
(13) FIG. 6A is a transparent view of a structure obtained after a primary molding step in the production process of an optical distance measuring apparatus of a third embodiment of the present invention;
(14) FIG. 6B is a top view of a structure of the optical distance measuring apparatus in process of production after a secondary molding step following the step of FIG. 6A;
(15) FIG. 6C is a transparent view of the structure of FIG. 6B;
(16) FIG. 7 is a sectional view taken along line B-B of FIG. 6C;
(17) FIG. 8 is a diagram showing the principle of the optical distance measuring apparatus;
(18) FIG. 9 is a diagram for explaining the problem due to the temperature change of the optical distance measuring apparatus;
(19) FIG. 10 shows a prior art optical distance measuring apparatus;
(20) FIG. 11 shows a prior art optical distance measuring apparatus;
(21) FIG. 12 shows a prior art optical distance measuring apparatus;
(22) FIG. 13A shows a prior art optical distance measuring apparatus;
(23) FIG. 13B shows a prior art optical distance measuring apparatus;
(24) FIG. 14 shows a prior art optical distance measuring apparatus;
(25) FIG. 15A is a sectional view for explaining a production process of a prior art optical distance measuring apparatus;
(26) FIG. 15B is a sectional view for explaining the production process of the prior art optical distance measuring apparatus;
(27) FIG. 15C is a sectional view for explaining the production process of the prior art optical distance measuring apparatus;
(28) FIG. 15D is a sectional view for explaining the production process of the prior art optical distance measuring apparatus;
(29) FIG. 15E is a sectional view for explaining the production process of the prior art optical distance measuring apparatus;
(30) FIG. 15F is a sectional view for explaining the production process of the prior art optical distance measuring apparatus;
(31) FIG. 16A is a top view of FIG. 15B;
(32) FIG. 16B is a top view of FIG. 15D;
(33) FIG. 16C is a transparent view of the structure of FIG. 16B;
(34) FIG. 17A is a sectional view taken along line A-A of FIG. 16C; and
(35) FIG. 17B is a sectional view taken along line B-B of FIG. 16C.
DESCRIPTION OF EMBODIMENTS
(36) The present invention will be described below by embodiments shown in the drawings.
(37) FIGS. 1A-1C show plan views of an optical distance measuring apparatus of a first embodiment of the present invention. Cross-sectional views of structures in production process steps in the present embodiment are same as the cross-sectional views shown in FIGS. 15A-15F. More specifically, FIG. 1A is a transparent view of a primary molded body obtained after the primary molding process. As shown in FIG. 1A, in the optical distance measuring apparatus, a light emitting header 2 mounted with a light emitting element 1 is connected, or joined with a light receiving header 4 mounted with a light-receiving element 3, which makes it possible to prevent expansion of the interval or spacing between the light emitting and receiving elements 1 and 3 resulting from expansion of the package due to influence of the temperature and humidity. Arranged on opposite sides of a connecting part 6 of the light emitting and receiving headers 2 and 4 are first reinforcing terminals 7 and 8 as first terminals which extend in opposite directions generally orthogonal to a direction in which the connecting part 6 of the light emitting and receiving headers 2 and 4 extends. The first reinforcing terminals 7 and 8 are joined to the light receiving header 4.
(38) FIG. 1B is a top view of a structure of the optical distance measuring apparatus in process of production after a secondary molding step following the step of FIG. 1A, and FIG. 1C shows a transparent view of FIG. 19. Further, FIG. 2A is a sectional view taken along line A-A of FIG. 1C and FIG. 2B is a sectional view taken along line B-B of FIG. 1C.
(39) In this embodiment, as shown in FIG. 2A, the first reinforcing terminals 7 and 8 are connected, or joined to the light receiving header 4, and are taken out to the outside of the package. Also, each of the first reinforcing terminals 7, 8 has a fixed portion 12, 13. These fixed portions 12 and 13 are fixed by the secondary molding. In addition, as shown in FIGS. 1B and 2B, a light emission side primary molded body (a light permeable resin body) 17 is covered with a light blocking secondary molded body (a first light blocking resin body) 21, except for a region in which a light beam emitted from the light emitting element 1 goes out. A light reception side primary molded body (a light permeable resin body) 18 is also covered with the light blocking secondary molded body (the first light blocking resin body) 21, except for a region in which a reflected light beam enters. Placed above the secondary molded body 21 is a lens frame 23 formed of a metal such as 42 alloy. A light emitting lens 29 (see FIG. 2B) formed of a light permeable resin and a light receiving lens 25 formed of a light permeable resin are formed on the lens frame 23.
(40) Further, as shown in FIG. 2A, the lens frame 23 with the lenses 25, 29 and the secondary molded body 21 are covered with a tertiary molded body (a second light blocking resin body) 30 formed of a light blocking resin so as to be fixed.
(41) As shown in FIG. 2B, at the time of reflow, a light blocking wall 35 between the light receiving and emitting parts is expanded significantly, so that stress tends to act in the directions indicated by arrows in the figure. However, in this embodiment, as shown in FIG. 2A, the light receiving header 4 is fixed by the secondary molded body 21 through the first reinforcing terminals 7 and 8, a lead frame 9 (see FIG. 1A) is prevented from warping. Therefore, even after reflow, it is possible to prevent relative positional relationship between the light emitting and receiving elements 1 and 3 and the light emitting and receiving lens 25 and 29 from being shifted, as a result of which a measured distance value is prevented from being changed after the reflow.
(42) In addition, referring to FIGS. 1A and 2B, each of the first reinforcing terminals 7 and 8 has a portion 90, 91 which underlays the light blocking wall 35 in a direction substantially orthogonal to the extending direction of the connecting part 6. In this way, the first reinforcing terminals 7 and 8 are placed in an area near the light blocking wall 35 between the light emitting and receiving elements 1 and 3, which area is subject to a largest stress due to the expansion, which is a factor of warpage of the lead frame 9. As a result of the provision of the first reinforcing terminals 7 and 8, warpage of the lead frame 9 is effectively prevented. In this embodiment, the first reinforcing terminals 7 and 8 are placed so as to underlap the light blocking wall 35 generally orthogonally to the direction in which the connecting part 6 extends, but only have to be placed near the light blocking wall to effectively prevent the warpage of the lead frame.
(43) FIGS. 3A-3C are plan views of an optical distance measuring apparatus according to a second embodiment of the present invention. More specifically, FIG. 3A is a transparent view of a structure obtained after a primary molding step, FIG. 3B is a top view of a structure after a secondary molding step following the step of FIG. 3A, and FIG. 3C is a transparent view of the structure of FIG. 3B. In the second embodiment, description is focused on features in which the second embodiment differs from the first embodiment.
(44) As shown in FIG. 3A, in the second embodiment, a lead frame 80 has a plurality of second reinforcing terminals 40 as second terminals. After the primary molding process, the plurality of second reinforcing terminals 40 extend in a direction substantially orthogonal to a direction of extension of a connecting part 81 of light receiving and emitting headers 39 and 41. Each second reinforcing terminal 40 is joined to the light emitting header 41. In the second embodiment, in addition to the light receiving header 39, the light emitting header 41 is also fixed by a secondary molded part 82 (see FIG. 3B) as the first light blocking resin body. According to the second embodiment, it is possible to further prevent warping due to the expansion of the package caused by reflow.
(45) FIGS. 4A-4C are plan views of an optical distance measuring apparatus according to a third embodiment of the present invention. More specifically, FIG. 4A is a transparent view of a structure obtained after a primary molding step, FIG. 4B is a top view of a structure after a secondary molding step following the step of FIG. 4A, and FIG. 4C is a transparent view of the structure of FIG. 4B. In the third embodiment, description is focused on features in which the third embodiment differs from the first embodiment.
(46) As shown in FIG. 4A, in the third embodiment, a lead frame 54 has a third reinforcing terminal 50 as a third terminal. The third reinforcing terminal 50 extends substantially in a direction in which a connecting part 56 between a light receiving header 49 and a light emitting header 51 extends. The third reinforcing terminal 50 has an extended portion 68 on one side of the light receiving header 49 opposite from the light emitting header 51. The third reinforcing terminal 50 is joined to the light receiving header 49.
(47) FIG. 5 is a sectional view taken along line B-B of FIG. 4C. As shown in FIG. 5, the third reinforcing terminal 50 includes a fixed portion 55 fixed to a second molded body 58 as a first light blocking resin body. According to the third embodiment, the fixed portion 55 of the third reinforcing terminal 50, which is connected to the light receiving header 49, is fixed by the second molded body 58. This results in increase in the number of fixed points even at end portions of the lead frame 54. Therefore, when stress due to the package expansion acts during the reflow process, it is possible to more securely prevent the lead frame 54 from warping.
(48) FIGS. 6A-6C are plan views of an optical distance measuring apparatus of a fourth embodiment of the present invention. Specifically, FIG. 6A is a transparent view of a structure obtained after a primary molding step, FIG. 6B is a top view of a structure after a secondary molding step following the step of FIG. 6A, and FIG. 6C is a transparent view of the structure of FIG. 6B. In the fourth embodiment, description is focused on features in which the fourth embodiment differs from the first embodiment.
(49) As shown in FIG. 6A, in the fourth embodiment, a lead frame 69 has a fourth reinforcing terminal 60 as a fourth terminal. The fourth reinforcing terminal 60 extends substantially in a direction in which a connecting part 83 between a light receiving header 59 and a light emitting header 61 extends. The fourth reinforcing terminal 60 has an extended portion 98 on one side of the light emitting header 61 opposite from the light receiving header 59. The fourth reinforcing terminal 60 is connected to the light emitting header 61.
(50) FIG. 7 is a sectional view taken along line B-B of FIG. 6C. As shown in FIG. 7, the fourth reinforcing terminal 60 includes a fixed portion 65 fixed to a second molded body 66 as a first light blocking resin body. According to the fourth embodiment, the fixed portion 65 of the fourth reinforcing terminal 60, which is connected to the light emitting header 61, is fixed by the secondary molded body 66. This results in increase in the number of fixed points even at end portions of the lead frame 69. Therefore, when stress due to the package expansion acts during the reflow process, it is possible to more securely prevent the lead frame 69 from warping.
(51) Several embodiments of the optical distance measuring apparatus of the present invention have been described above. The optical distance measuring apparatus according to the present invention can have good performance such as an increased heat resistance performance. Also, it is possible to mount a large number of optical distance measuring apparatuses to electronic apparatuses in a short time and with ease by reflow. Therefore, if the optical distance measuring apparatus is incorporated in a personal computer (PC), it can be detected correctly whether a person is present in front of the PC. If it is detected that there is no person in front of the PC, the PC may be brought into a sleep mode. In this way, it is possible to carry out energy saving efficiently. If the optical distance measuring apparatus is incorporated in a self-travelling cleaner, it is possible to accurately detect obstacles and steps. If the optical distance measuring apparatus is incorporated in an electronic kitchen appliance, it is possible to provide a non-contact switch for making ON/OFF operations of the kitchen appliance in a non-contact manner. Furthermore, with the optical distance measuring apparatus installed in an electronic apparatus, it is possible for the electronic apparatus to accurately detect a distance to an operator's hand to perform operations such as a volume control operation in a non-contact manner. Thus, it is possible for the electronic apparatus to suitably perform such operations when the operator has wet hands or dirty hands.
(52) It goes without saying that two or more of the first to the fourth embodiments may be combined into a new embodiment. It also goes without saying that two or more features may be picked up from all of the embodiments and the variations/modifications described herein, and combined into a new embodiment.
REFERENCE SIGNS LIST
(53) 1 light-emitting element 2, 41, 51, 61 light emitting header 3 light-receiving element 4, 39, 49, 59 light receiving header 6, 56, 81, 83 connecting part 7, 8 first reinforcing terminal 9, 54, 69, 80 lead frame 21, 58, 66, 82 secondary molded body 35 light blocking wall 40 second reinforcing terminal 50 third reinforcing terminal 55 fixed portion of the third reinforcing terminal 60 fourth reinforcing terminal 65 fixed portion of the fourth reinforcing terminal
