Abstract: A land grid array socket comprises an insulative housing having a plurality of contacts. The insulative housing has a top surface for receiving a land grid array package. A cover member is pivotally mounted on a first end of the insulative housing. The cover member is pivotal between an open position and a closed position where the cover member presses the land grid array package toward the top surface of the insulative housing so that the land grid array package electrically connects to the contacts. A lever is pivotally mounted on a second end of the insulative housing. The lever has a locking portion for locking the cover member in the closed position. A metallic reinforcing plate is positioned on a bottom surface of the housing. The metallic reinforcing plate extends between the first end and the second end of the insulative housing.

Abstract: The depth and a relative dimensional factor of a defect present in the interior of a silicon wafer are measured, and the number of such defects is calculated. A laser beam having a larger energy than the band gap of silicon is radiated obliquely to the semiconductor wafer and a scattered beam from a defect present in a subsurface layer of the wafer is detected by an image pick-up device. The temperature of the wafer is changed to at least two temperatures of T1 and T2 or to any one of plural temperatures by means of a heater and the intensity of a scattered beam is measured. It is taken into account that the light absorbance of silicon and the penetration depth of light in silicon vary depending on temperature, to determine the depth and a relative dimensional factor of an internal defect which causes scattering of light, as well as the number of such crystal defects.

Abstract: A land grid array socket contact structured so that the size of a resilient contact in a direction perpendicular to a base plate in a vicinity of a root of the resilient contact is minimized so that an arrangement pitch in this direction may be reduced and the resilient contact may be displaced by a large amount to minimize connection resistance. The land grid array socket contact has a base plate with side walls. A resilient contact extends parallel to the base plate. The resilient contact is attached to at least one of the side walls of the base plate by a curved section angled approximately 180 degrees from the at least one side wall. The resilient contact has a free end for contacting a contact pad. A board terminal extends from a lower end of the base plate for connection to a circuit board.

Abstract: The object of the present invention is to provide a card connecting structure and a card connector used in the same which have a minimum width that allows the guidance of the card at the time of insertion and the fastening of the received card, and that makes it possible to satisfy specifications in which space for fastening is not provided on both sides of the card, and which can sufficiently protect the solder-connected parts of the contacts. The card connecting structure comprises a card 40 that has contact pads 41 on one end, and a card connector 1 that receives this end of the card 40. Fastening means 50 that fasten the card 40 to the circuit board are disposed on the other end of the card 40 from the contact pads. Metal guide members 30 that guide the card 40 are disposed on both sides of the housing 10 (in the lengthwise direction) of the card connector 1.

Abstract: A process for producing a styrenic resin with a small content of low molecular weight components, comprising a continuous anionic polymerization process wherein a raw material system having the following composition (A) is continuously fed, either collectively or in a divided manner, from one end of a reactor tank R1 having a back mixing flow and the product system is continuously discharged from the other end of the reactor tank R1, the internal temperature of the reactor tank R1 being controlled to a range of 40-120° C., the average proportion of styrene monomers to the sum total of the styrene monomers, hydrocarbon solvent and styrenic polymers present in the reactor tank R1 being controlled to less than 10 wt. %, and the resulting styrenic polymer solution being devolatilized and dried: 1 (A) Styrene monomer 1.0 kg Hydrocarbon solvent 0.1-3 kg Organolithium compound 0.

Abstract: A magneto-optical recording medium 11 is irradiated with a reproducing light beam 13 so that only a minute magnetic domain 313b, which is subjected to recording in a recording layer 18 and which is smaller than ½ of a spot radius of the recording light beam 13, is selected by a gate layer 17 and transferred to a magnetic domain-magnifying and reproducing layer 3. The magnetic domain transferred to the magnetic domain-magnifying and reproducing layer 3 is magnified by using a magnifying and reproducing magnetic field 411 of an alternating magnetic field. A large reproduction signal is obtained from the magnified magnetic domain 419, and the minute magnetic domain can be subjected to reproduction at a high resolving power and at a high S/N ratio. The magnified magnetic domain 419 is reduced by using a reducing reproducing magnetic field 415 of the alternating magnetic field. The gate layer 17 has a thickness which is not less than a thickness of a magnetic wall of the magnetic domain.

Abstract: A ball grid array connector having an insulative housing with a plurality of contacts in electrical connection with corresponding solder balls that protrude from a surface of the housing. The solder balls form a soldering region for attachment to a circuit board. The housing has a center of gravity biased from a center of the soldering region, and a positional compensation member is attached to the housing and the circuit board. The positional compensation member prevents the housing from becoming inclined with respect to the circuit board when the solder balls are attached to the circuit board and prevents the housing from becoming inclined with respect to an electronic part when the electronic part is mounted to the housing on a side opposite from the circuit board.

Abstract: An IC socket is provided which can absorb the difference in linear expansion coefficient between the housing and the circuit board, and thus prevent the occurrence of solder cracking and warping, without lowering the strength of the housing. First slits which have bottoms and which extend from the upper surface of the housing toward the undersurface of the housing are formed between specified rows of pin receiving openings which are formed in the upper surfaces of contact press-fitting accommodating holes that are arranged in the form of a matrix. These holes pass entirely through the housing from the upper surface to the undersurface. Second slits which have bottoms and which extend from the undersurface of the housing toward the upper surface of the housing are formed between specified rows of solder ball receiving cavities formed in the undersurfaces of the contact receiving cavities in positions where the first slits are not formed.

Abstract: A magneto-optical recording medium 11 has, in order from the laser irradiation side, a second auxiliary magnetic film 4, first auxiliary magnetic film 5, and magneto-optical recording film 6. First and second auxiliary magnetic films 4 and 5 change from in-plane magnetization to perpendicular magnetization when their respective critical temperatures TCR1 and TCR2 are exceeded. The Curie temperatures TC0, TC1 and TC2 of the magneto-optical recording film and the first and the second auxiliary magnetic films 4, 5 and their critical temperatures TCR1 and TCR2 satisfy the relationship: room temperature<TCR2<TCR1<TC0, TC1,TC2. The first auxiliary magnetic layer has a film thickness greater than the thickness of the magnetic wall. In response to irradiation by the reproducing light beam, recording magnetic domain 22 of magneto-optical recording film 6 is transferred, with size reduction, to first auxiliary magnetic film 5 and is then transferred, with magnification, to second auxiliary magnetic film 4.

Abstract: The male connector 1 has a metal shielding shell 4 that accommodates a housing 2 and a synthetic resin enclosure 8 that covers approximately the rear half of this shielding shell 4. Fastening parts 40 and protruding parts 42 are formed by stamping in the upper-side shell half-body 4a. A metal latching arm 44 which is formed with the approximate shape of a shallow inverted V, and which has an engaging part 54, is disposed between these fastening parts 40 and protruding parts 42. The latching arm 44 can be pressed by means of a finger-catch part 68. This configuration obtains the desired shielding performance while maintaining a compact size in a shielded electrical connector assembly.

Abstract: An IC socket is provided which can absorb the difference in linear expansion coefficient between the housing and the circuit board, and thus prevent the occurrence of solder cracking and warping, without lowering the strength of the housing. First slits which have bottoms and which extend from the upper surface of the housing toward the undersurface of the housing are formed between specified rows of pin receiving openings which are formed in the upper surfaces of contact press-fitting accommodating holes that are arranged in the form of a matrix. These holes pass entirely through the housing from the upper surface to the undersurface. Second slits which have bottoms and which extend from the undersurface of the housing toward the upper surface of the housing are formed between specified rows of solder ball receiving cavities formed in the undersurfaces of the contact receiving cavities in positions where the first slits are not formed.

Abstract: A compact ZIF type socket is provided having the durability to withstand numerous movements of the slider. The ZIF type IC socket 1 consists of a base housing assembly 10 that accommodates numerous contacts, and a cover housing assembly 40 that can slide over the base housing assembly 10. The cover housing assembly 40 is caused to move in relative terms by inserting a plate-form tool 99 into tool insertion holes 65 and 85 respectively formed in a metal supporting plate 60 on the side of the base housing assembly 10 and a metal supporting plate 80 on the side of the cover housing assembly 40, and rotating this tool 99. The action points of the tool insertion holes 65 and 85 contacted by the tool 99 are formed as circular-arc-form projections 75, 76, 95 and 96. Accordingly, the force of the tool 99 can be transmitted to the base housing assembly 10 and cover housing assembly 40 without causing indentation or damage, etc.

Abstract: A tilt switch includes a pair of contact elements; and at least one ball member which rolls along a path defined between the contact elements. The contact elements are disposed facing each other with a distance therebetween, as measured at one end, which is greater than the diameter of the ball member, and as measured at the other end, which is slightly smaller than the diameter of the ball member. Tilting of the tilt switch is electrically detected through detection of whether or not the ball member is held between the contact elements.

Abstract: A magneto-optical recording medium 11 is irradiated with a reproducing light beam 13 so that only a minute magnetic domain 313b, which is subjected to recording in a recording layer 18 and which is smaller than ½ of a spot radius of the recording light beam 13, is selected by a gate layer 17 and transferred to a magnetic domain magnifying and reproducing layer 3. The magnetic domain transferred to the magnetic domain-magnifying and reproducing layer 3 is magnified by using a magnifying and reproducing magnetic field 411 of an alternating magnetic field. A large reproduction signal is obtained from the magnified magnetic domain 419, and the minute magnetic domain can be subjected to reproduction at a high resolving power and at a high SIN ratio. The magnified magnetic domain 419 is reduced by using a reducing reproducing magnetic field 415 of the alternating magnetic field. The gate layer 17 has a thickness which is not less than a thickness of a magnetic wall of the magnetic domain.

Abstract: A magneto-optical recording medium includes a reproducing layer. When a laser beam is irradiated to the magneto-optical recording medium, a magnetic domain in a recording layer is transferred, through enlargement, to a reproducing layer increased in temperature. The magneto-optical recording medium further includes a calibration area that has a calibration magnetic domain recorded in a predetermined pattern in the recording layer. In a reproducing apparatus, a laser beam of an optical head is adjusted in output depending upon a reproduced signal obtained by reproducing the calibration magnetic domain.

Abstract: A magneto-optical recording medium which includes a reproducing layer. When a laser beam is irradiated to the magneto-optical recording medium, a magnetic domain in a recording layer is transferred, through enlargement, to a reproducing layer increased in temperature. The magneto-optical recording medium further includes a calibration area that has a calibration magnetic domain recorded in a predetermined pattern in the recording layer. In a reproducing apparatus, a laser beam of an optical head is adjusted in output depending upon a reproduced signal obtained by reproducing the calibration magnetic domain.

Abstract: A paging processing system in a virtual storage device of a computer composed of a plurality of computers connected directly or over a network including page data reception checking portion for notifying other computer which conducts page-out processing of the number of free physical pages of a physical memory in its own computer, page data reception/transmission portion for conducting processing of receiving page data from other computer and processing of returning received data, page data transmission checking portion for selecting a computer as a page data transmission destination based on the number of free physical pages notified by the page data reception checking portion, page data transmission/reception portion for conducting transmission processing of transmitting, to the other computer selected, page data of a virtual page to be paged out and reception processing when transmitted page data is returned, and page management portion for controlling each of the portion to manage a correspondence relatio

Abstract: Electrical connector (1) comprising a first contact member (10) having an arcuate contact surface (14a) that engages an electrical wire (3), a second contact member (40) has a connecting portion (50) and a pressing portion (48) that presses a free end (30) of the contact section (14). Insulating housing (60) has a first cavity (62) in which a wire-engaging surface (74) is located, and a second cavity (66) which communicates with the first cavity (62). When the first contact member (10) is inserted into the first cavity (62) and the second contact member (40) is press-fitted in the second cavity (66) in a state in which the electrical wire 3 is disposed between the wire-engaging surface (74) and the contact section (14), the pressing portion (48) presses the free end (30) so that the contact section (14) is caused to make electrical connection with the electrical wire (3).

Abstract: In a measurement method for measuring the epitaxial film thickness of a multilayer epitaxial wafer, a reflectivity spectrum of a multilayer epitaxial wafer having at least two epitaxial layers of different electric characteristics is measured by using infrared radiation in a far infrared region of at least 500 cm.sup.-1 or less, and frequency-analysis is performed on the reflection spectrum thus obtained by a maximum entropy method, and the film thickness of each epitaxial layer is calculated on the basis of the analysis spectrum thus obtained.

Abstract: A silicon wafer measuring method includes: (a) a first step of measuring a light transmission characteristic (I.sub.OBS) of the pulled silicon wafer by utilizing parallel polarized light incident at the Brewster angle into the pulled silicon wafer, (b) a second step of measuring a light transmission characteristic (I.sub.O) of a floating zone silicon wafer functioning as a reference silicon wafer by utilizing parallel polarized light incident at the Brewster angle into the floating zone silicon wafer, and (c) a third step of calculating a substitutional carbon concentration ?C.sub.SC ! on the basis of the light transmission characteristic (I.sub.OBS) of the pulled silicon wafer measured during the first step and the light transmission characteristic (I.sub.O) of the floating zone silicon wafer measured during the second step, (d) a fourth step of comparing the substitutional carbon concentration ?C.sub.