Abstract:
The invention provides an aging socket, an aging cassette and an aging apparatus with which an aging system of a very low cost can be constructed and aging can be performed for any number of inspection object parts. The aging socket includes a base on which a mounting portion on which an imaging object part can be mounted is formed, and a heater and a temperature regulator incorporated in the base. A plurality of such aging sockets are disposed in a matrix on the aging cassette. One or a plurality of such cassettes on which such sockets are mounted are mounted in position into slots of the aging apparatus. Consequently, aging of any number of aging object parts mounted on the sockets of one or more cassettes can be performed by the aging apparatus.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to an aging socket and an aging cassette suitably applied to a small electronic part such as a semiconductor laser device and an aging device for performing aging for a small electronic part. 
     An aging socket, an aging cassette and an aging apparatus which are conventionally known are shown in FIGS. 7 to  13 B. 
     First, a semiconductor laser coupler which is one of aging object parts to be aged is described briefly with reference to FIG.  7 . 
     The semiconductor laser coupler D shown is constructed such that a laser device body mounted on a circuit board is accommodated in a package  1  of a shape of a parallelepiped which has an opening  2  at a central portion of the top thereof while a pair of wedge-shaped notches  3  are formed in the middle of a pair of opposing sides thereof such that a laser beam is emitted from the opening  2  and then introduced into the opening  2  after it is reflected by a reflecting object so that some signals may be detected by the semiconductor laser coupler D. 
     An aging apparatus and an aging cassette are shown in FIGS. 8 and 9, respectively. Referring to FIGS. 8 and 9, the aging cassette (hereinafter referred to merely as “cassette”)  20  and the aging apparatus  10  are used such that the semiconductor laser coupler D as described above with reference to FIG. 7 is placed onto the cassette  20  and then the cassette  20  is placed onto the aging apparatus  10  and then heated to a temperature of 60° C. to 70° C. to evaluate a condition of deterioration of various characteristics of the semiconductor laser coupler D. 
     The aging apparatus  10  includes a housing  11  of a large size and has a constant temperature bath function of keeping the inside thereof constant at the temperature mentioned above. The inside of the aging apparatus  10  is partitioned like a matrix to form a plurality of slots  12  therein. Further, though not shown, a common heater and fan are built in the aging apparatus  10  such that hot air heated by the heater is blasted into the inside of the housing  11  to simultaneously heat all cassettes  20  accommodated in the slots  12  to a substantially equal temperature while the temperature is controlled so as to be fixed by a temperature regulator also which is built in the aging apparatus  10 . Further, the aging apparatus  10  has a front panel section  13  on the right side in FIG. 8, and a temperature display apparatus  14  and a power supply switch  15  are provided at an upper portion of the front panel section  13 . Further, a circuit breaker  16  and so forth are provided at a lower portion of the front panel section  13 . 
     It is to be noted that, although, during aging of the aging apparatus  10 , the front of the aging apparatus  10  is closed up with a door to keep the inside of the aging apparatus  10  at the constant temperature, in FIG. 8 the aging apparatus  10  is shown with the door removed. Further, in FIG. 8, the aging apparatus  10  is shown in a state wherein the cassette  20  shown in FIG. 9 is inserted in each of the slots  12  described above. 
     The cassette  20  is formed in such a structure as shown in FIGS. 9 to  12 . Referring to FIGS. 9 to  12 , the cassette  20  includes a body  21  and a lid member  22  connected to each other by a pair of hinges  23 . The body  21  receives a plurality of semiconductor laser couplers D as aging object parts thereon, and the lid member  22  has a plurality of light receiving elements R, which each receives a laser beam, incorporated therein corresponding to the semiconductor laser couplers D. 
     While FIG. 9 shows the cassette  20  where semiconductor laser couplers D are mounted on the body  21 , each of the semiconductor laser couplers D is received in a socket  30  shown in FIGS. 10 to  13 B. Before the structure of the socket  30  is described, the structure of the cassette  20  is described. A plurality of sockets  30  are incorporated in an arrangement of a matrix on a face of the body  21  of the cassette  20  which opposes to the lid member  22 . A power supply electrode, a ground electrode and a signal transmission/reception electrode are incorporated in each of the sockets  30 , and the electrodes of the sockets  30  are connected to an electronic circuit board  24  disposed below the sockets  30 . Part of the electronic circuit board  24  is led out toward the hinged side  23  of the cassette  20  and serves as a plug-in terminal  24 A when the cassette  20  is inserted into a slot  12  of the aging apparatus  10 . 
     Meanwhile, a plurality of circular holes  25  are formed at portions of a surface of the lid member  22  adjacent the body  21  in an opposing relationship to the sockets  30 . Further, a hold down plate  26  is disposed on the surface of the lid member  22  adjacent the body  21  such that it can hold down the semiconductor laser couplers D when the lid member  22  is closed while the semiconductor laser couplers D are received in the socket  30 , and the light receiving elements R are disposed in the circular holes  25 . Also various electrodes of the light receiving elements R are connected to an electronic circuit of a electronic circuit board  27  disposed behind them. Part of the electronic circuit board  27  is led out to the hinged side  23  of the cassette  20  similarly and serves as another plug-in terminal  27 A when the cassette  20  is inserted into a slot  12  of the aging apparatus  10 . 
     A U-shaped handle  28 A is mounted on an end face of the body  21  remote from the hinges  23 , and another U-shaped handle  28 B of an equal size is mounted on a corresponding end face of the lid member  22 . 
     The socket  30  is particularly shown in FIGS. 13A and 13B. Referring to FIGS. 13A and 13B, the socket  30  has a cylindrical portion  31  of a comparatively great thickness at a central portion thereof. An upper flange  32  in the form of a disk having a comparatively small thickness is formed horizontally at an upper end of the cylindrical portion  31 , and a mounting flange  33  in the form of a disk having a comparatively great thickness is formed horizontally at a lower end of the cylindrical portion  31 . Consequently, the socket  30  is formed as a base  34  of a tubular structure having a U-shaped cross section. A pair of electrode pins  36 A and  36 B are positioned in an opposing relationship on an inner circumferential face of a hollow portion  35  of a horizontally circular section at a central portion of the base  34  and are led out downwardly of the base  34  from a receiving face of the base  34  for a semiconductor laser coupler D. 
     Further, a pair of positioning pins  37 A and  37 B are embedded in the base  34  such that they are held in contact with outer arcuate faces of the electrode pins  36 A and  36 B and extend upwardly a little above the top face of the base  34 . The distance between inner arcuate faces of the positioning pins  37 A and  37 B is set corresponding to the distance between the pair of notches  3  formed on the package  1  for a semiconductor laser coupler D. 
     Four fixing screws  38  are formed in the mounting flange  33 , and four through-holes  39  are formed in the upper flange  32  and positioned above the mounting flange  33 . Thus, a screwdriver may be inserted in any of the through-holes  39  and screw a fixing screw into the fixing screw  38  to fasten the base  34  to a mounting member of the body  21  side. In FIGS. 13A and 13B, a semiconductor laser coupler D is shown mounted on the socket  30 . 
     The conventional aging apparatus  10  and cassette  20  are constructed in such structures as described above. In order to perform aging of semiconductor laser couplers D using the aging apparatus  10  and the cassette  20 , the lid member  22  of the cassette  20  is opened first, and a semiconductor laser coupler D is placed into each of the sockets  30  disposed on the body  21  of the cassette  20  such that the positioning pins  37 A and  37 B are inserted into the notches  3  of the semiconductor laser coupler D until the semiconductor laser coupler D is brought into contact with the electrode pins  36 A and  36 B. 
     Then, a large number of such cassettes  20  as described above on each of which a large number of semiconductor laser couplers D are mounted in such a manner as described above are inserted into the slots  12  of the aging apparatus  10  until the plug-in terminals  24 A and  27 A projecting from the cassettes  20  are fitted into sockets (not shown) mounted at interior portions of the slots  12  so that they are mounted in position. Then, the door (not shown) of the aging apparatus  10  is closed. 
     Thereafter, the power supply switch  15  of the aging apparatus  10  is turned on so that the inside of the aging apparatus  10  is heated until such a predetermined fixed temperature as described above is reached, and the inside of the aging apparatus  10  is regulated by the temperature regulators  13  so that the individual cassettes  20  may be kept at the predetermined fixed temperature. 
     Simultaneously, power is supplied to each of the semiconductor laser couplers D through the plug-in terminal  24 A, and power is supplied also to the light receiving elements R corresponding to the semiconductor laser couplers D through the plug-in terminal  27 A while data signals produced by the individual light receiving elements R from laser light received from the individually corresponding semiconductor laser couplers D are inputted from the plug-in terminal  27 A to a computer (not shown) connected to the aging apparatus  10 . Consequently, the computer processes the inputted data signals to detect and record characteristic variations of the individual semiconductor laser couplers D. 
     Such aging is performed to examine whether or not the individual semiconductor laser couplers D are good or whether or not semiconductor laser couplers D are good for each manufacture lot. 
     However, the aging apparatus  10  must produce a predetermined temperature profile after all cassettes  20  are set into it because the aging apparatus  10  itself functions as a constant temperature bath. 
     Further, the aging apparatus  10  itself is considerably large in size and is very high in price. 
     Furthermore, in the conventional aging apparatus  10 , the body serving as a constant temperature bath is controlled using a single temperature regulator. Consequently, each aging operation must be performed with cassettes  20  received in all of the slots  12  of the aging apparatus  10 . Accordingly, the operation efficiency is low. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an aging socket, an aging cassette and an aging apparatus with which an aging system of a very low cost can be constructed. 
     It is another object of the present invention to provide an aging socket, an aging cassette and an aging apparatus with which aging can be performed for any number of inspection object parts. 
     In order to attain the objects described above, according to an aspect of the present invention, there is provided an aging socket, including a base on which a mounting portion on which an aging object part can be mounted is formed, a heater for heating an aging object part mounted on the mounting portion, and a temperature sensor for detecting a temperature of the mounting portion, a temperature of an aging object part mounted on the mounting portion and being heated or a temperature of the heater, the heater and the temperature sensor being incorporated in the base in such a manner as to be opposed to the mounting portion. 
     With the aging socket, an aging object part mounted on the aging socket can be heated directly. 
     According to another aspect of the present invention, there is provided an aging cassette, including a body, a plurality of sockets disposed on the body and each including a base on which a mounting portion on which an aging object part can be mounted is formed, a heater for heating an aging object part mounted on the mounting portion, and a temperature sensor for detecting a temperature of the mounting portion, a temperature of an aging object part mounted on the mounting portion and being heated or a temperature of the heater, the heater and the temperature sensor being incorporated in the base in such a manner as to be opposed to the mounting portion, and an electronic circuit board built in the body and including a power supply circuit by which terminals of the heaters and the temperature sensors mounted on the sockets are connected to individual power supplies. 
     With the aging cassette, all of aging object parts mounted on the aging cassette can be heated all at the same time or for each group or else individually to perform aging of the same. Consequently, characteristic states of the individual aging object parts can be evaluated. 
     According to a further aspect of the present invention, there is provided an aging apparatus, including a body on which a plurality of slots each capable of receiving an aging cassette are formed, each of the aging cassettes having a body, a plurality of sockets disposed on the body and each including a socket body, a plurality of sockets disposed on the socket body of the socket and each including a base on which a mounting portion on which an aging object part can be mounted is formed, a heater for heating an aging object part mounted on the mounting portion, and a temperature sensor for detecting a temperature of the mounting portion, a temperature of an aging object part mounted on the mounting portion and being heated or a temperature of the heater, the heater and the temperature sensor being incorporated in the base in such a manner as to be opposed to the mounting portion, and an electronic circuit board built in the body and including a power supply circuit by which terminals of the heaters and the temperature sensors mounted on the sockets are connected to individual power supplies, and a start switch and a temperature regulator incorporated in each of the slots. 
     Preferably, the aging apparatus further comprises a temperature indicator incorporated in each of the slots. 
     With the aging apparatus, it need not be formed as a constant temperature bath, and consequently, it can be formed at a very low cost. Further, aging of any number of aging cassettes which are set in the slots of the aging apparatus can be started individually or for each group or else for all of them to effect temperature regulation. Accordingly, aging object parts can be evaluated individually, and aging can be performed irrespective of whether the quantity of aging object parts is great or small. 
     The above and other objects, features and advantages of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings in which like parts or elements denoted by like reference symbols. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational view of an aging apparatus to which the present invention is applied; 
     FIG. 2 is a perspective view showing an appearance of an aging cassette to which the present invention is applied; 
     FIG. 3 is a top plan view showing the aging cassette shown in FIG. 2 with part of a lid member cut away; 
     FIG. 4 is a schematic side elevational view partly in section showing a side face of the aging cassette shown in FIG. 3 as viewed from an arrow A; 
     FIG. 5 is a side elevational view of the aging cassette shown in FIG. 3 as viewed from an arrow B; 
     FIG. 6A is a top plan view showing a socket which is incorporated in the aging cassette shown in FIG. 2; 
     FIG. 6B is an enlarged sectional view taken along line A—A of FIG. 6A; 
     FIG. 7 is a top plan view schematically showing an example of a semiconductor laser coupler which is used popularly; 
     FIG. 8 is a front elevational view of a conventional aging apparatus; 
     FIG. 9 is a perspective view showing an appearance of a conventional aging cassette; 
     FIG. 10 is a top plan view showing the aging cassette shown in FIG. 9 with part of a lid member cut away; 
     FIG. 11 is a side elevational view partly in section showing the aging cassette shown in FIG. 10 as viewed from an arrow A; 
     FIG. 12 is a side elevational view of the aging cassette shown in FIG. 10 as viewed from an arrow B; 
     FIG. 13A is a top plan view showing a socket incorporated in the aging cassette shown in FIG. 9; and 
     FIG. 13B is an enlarged sectional view taken along line A—A of FIG.  13 A. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, there is shown an aging apparatus to which the present invention is applied. The aging apparatus is generally denoted at  50  and includes a housing  51 , the inside of which is partitioned in a matrix to form a plurality of slots  52 . In the interior of each of the slots  52 , a pair of sockets (not shown) into which two plug-in terminals of a cassette  60  which will be hereinafter described are inserted are provided. The sockets of the slots  52  are connected to a built-in or externally provided evaluation circuit (not shown) for supplying power to individual semiconductor laser couplers D mounted on bodies  61  of individual cassettes  60  and supplying power to individual light receiving elements R mounted on lid members  62  of the cassettes  60  and for evaluating states such as light emission characteristics of the semiconductor laser couplers D from signals generated from the light receiving elements R receiving laser beams emitted from the semiconductor laser couplers D. 
     The housing  51  has an opening formed on the right side in FIG. 1 of each of the slots  52 . In each of the openings, a power supply switch  53  for supplying power to a cassette  60  inserted in the corresponding slot  52 , a temperature regulator  54  for regulating the temperatures of semiconductor laser couplers D mounted in the individual sockets  30  of the cassette  60 , and a monitor  55  are mounted on the surface of a front panel. 
     Further, a front panel section  56  is provided on a right portion in FIG. 1 of the housing  51 , and a main power supply switch  57  is mounted at an upper portion of the front panel section  56  while a main circuit breaker  58  is mounted at a lower portion of the front panel section  56 . 
     Similarly to the conventional aging apparatus  10  described hereinabove, the aging apparatus  50  includes a door (not shown) for closing the front of the aging apparatus  50  to keep the inside of the aging apparatus  50  at a constant temperature during aging. In FIG. 1, the aging apparatus  50  is shown with the door removed. Further, in FIG. 1, the aging apparatus  50  is shown with the cassette  60  of FIG. 2 inserted in each of the slots  52  thereof. 
     Now, a cassette to which the present invention is applied is described with reference to FIGS. 2 to  5 . The cassette generally has a similar construction to that of the conventional cassette  20  described hereinabove, and like elements are denoted by like reference characters and overlapping description of them is omitted herein to avoid redundancy. 
     Referring first to FIG. 2, the cassette is generally denoted at  60 . The cassette  60  is similar to but different from the conventional cassette  20  in individual sockets  70  thereof. Referring to FIGS. 6A and 6B, each socket  70  is similar to but different from the conventional socket  30  described hereinabove with reference to FIGS. 13A and 13B in that a heater  71  is incorporated in the hollow portion  35  of the base  34  of the socket  70  such that an end portion thereof is exposed to a coupler receiving portion of the socket  70  so as to contact with a semiconductor laser coupler D when the semiconductor laser coupler D is placed on the coupler receiving portion of the socket  70  and that a temperature sensor  73  is incorporated in the socket  70  such that it is opposed to the heater  71  in the proximity of the coupler receiving portion of the socket  70 . For the heater  71 , for example, a solid-state element which makes use of a Peltier effect is suitably used, and a pair of terminals  72  extend from the heater  71 . Meanwhile, the temperature sensor  73  may be such an element as, for example, a thermocouple, and has a pair of terminals  74 , for indicating the temperature of sensor  73 . 
     While the temperature sensor  73  is preferably disposed as closely as possible to a heated semiconductor laser coupler D to detect the temperature of the semiconductor laser coupler D, if temperature correction is possible in advance, then the temperature sensor  73  may be disposed so as to detect the temperature of the coupler receiving portion or the temperature of the heater. 
     A plurality of such sockets  70  are disposed in a matrix on a cassette shown in FIGS. 2 to  5  to which the present invention is applied. Particularly, as seen in FIG. 4 in which the cassette  60  is shown partly in section, the terminals  72  of the heaters  71  are connected to a power supply circuit (not shown) of the electronic circuit board  24  built in the body  21  of the cassette  60 , and terminals  74  of the temperature sensors  73  are connected to a temperature control circuit (not shown) of the electronic circuit board  24 . Also the other sockets  70  are connected similarly in parallel to each other. 
     A large number of such cassettes  60  on each of which a large number of semiconductor laser couplers D are mounted in such a manner as described above are inserted into the slots  12  of the aging apparatus  50  until the plug-in terminals  24 A and  27 A projecting from each of the cassettes  60  are inserted into the sockets (not shown) mounted in the interior of the slots  12  to mount the cassettes  60  in position into the aging apparatus  50 . Then, the door not shown of the aging apparatus  50  is closed. 
     Then, the main power supply switch  57  and the individual power supply switches  53  of the aging apparatus  50  are turned on, and the semiconductor laser couplers D mounted on the sockets  70  in the individual cassettes  60  are controlled by the temperature regulators  54  through the temperature sensors  73  so that they may be kept at a predetermined fixed temperature. 
     Simultaneously, power is supplied to the semiconductor laser couplers D through the plug-in terminals  24 A while power is simultaneously supplied also to the light receiving elements R corresponding to the individual semiconductor laser couplers D through the plug-in terminals  27 A. Then, data signals produced by the light receiving elements R receiving laser beams generated from the corresponding semiconductor laser couplers D are inputted from the plug-in terminals  27 A to a computer (not shown) connected to the aging apparatus  50 . The computer processes the data signals to detect and record characteristic variations of the semiconductor laser couplers D and so forth. The data are also displayed on the individual monitors  55 . 
     Such aging as described above is performed to investigate whether or not the individual semiconductor laser couplers D are good or whether or not semiconductor laser couplers D are good for each manufacture lot. 
     The main power supply switch  57  need not necessarily be provided. In this instance, a power supply circuit may be provided by which, when the power supply switches  53  provided for the individual slots  52  are turned on, the semiconductor laser couplers D mounted on the individual sockets  70  in the slots  52  are heated by the heaters  71 . 
     Alternatively, such a power supply circuit that, when it is desired to mount the cassettes  60  into the slots  52  and perform aging, only if the main power supply switch  57  is turned on, all of the sockets  70  are energized to cause the heaters  71  to generate heat may be provided. 
     When aging of semiconductor laser couplers D described above is performed using a cassette  60  and the aging apparatus  50 , the cassette  60  need not be mounted in all of the slots  52  of the aging apparatus  50 . Since a heater  71  is incorporated in each of the sockets  70 , if one cassette  60  is mounted into one of the slots  52  and the power supply switch  53  provided for the slot  52  is turned on, then aging of semiconductor laser couplers D of the single cassette  60  can be performed. 
     Further, since a heater  71  is incorporated in each of the sockets  70 , even if the semiconductor laser coupler D as aging object parts is not mounted in all of the sockets  70  in one cassette  60 , or in an extreme case, even if only one semiconductor laser coupler D is mounted in one cassette  60 , it is possible to mount the cassette  60  into a slot  52  of the aging apparatus  50  and turn on the power supply switch  53  provided for the slot  52  to perform aging of the single semiconductor laser coupler D. 
     While, in the foregoing description, a semiconductor laser coupler is used as an aging object part, the aging object part is not limited to this, and the present invention can naturally be applied also to aging of a semiconductor device such as an ordinary IC, or some other electronic part or mechanical part. 
     While a preferred embodiment of the present invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.