Mitsubishi Electric

About: Mitsubishi Electric is a company organization based out in Ratingen, Germany. It is known for research contribution in the topics: Signal & Voltage. The organization has 23024 authors who have published 27591 publications receiving 255671 citations. The organization is also known as: Mitsubishi Electric Corporation & Mitsubishi Denki K.K..

Virtual image display device

Abstract: A virtual image display device includes a light source unit, a polarization switching unit, an image generation unit, an optical path unit and a projection unit. The polarization switching unit switches a polarization direction of a light beam emitted from the light source unit. The optical path unit includes a first optical path through which the light beam having the first polarization direction travels and a second optical path through which the light beam having the second polarization direction travels. A first virtual image is displayed at a first distance with the light beam that has traveled through the first optical path. A second virtual image is displayed at a second distance farther than the first distance with the light beam that has traveled through the second optical path.

Non-contact IC card with monitor for source power

Abstract: A non-contact type IC card includes a rectifier circuit for supplying a source voltage to respective circuits of an IC card based on the strength of radio waves received from a host computer. A reference voltage generating circuit generates a reference voltage. A comparison circuit compares the source voltage with the reference voltage. A control circuit prohibits the writing of data if the source voltage becomes less than the reference voltage.

640 x 480 pixel uncooled infrared FPA with SOI diode detectors

Abstract: This paper describes the structure and performance of a 25-micron pitch 640 x 480 pixel uncooled infrared focal plane array (IR FPA) with silicon-on-insulator (SOI) diode detectors. The uncooled IR FPA is a thermal type FPA that has a temperature sensor of single crystal PN junction diodes formed in an SOI layer. In the conventional pixel structure, the temperature sensor and two support legs for thermal isolation are made in the lower level of the pixel, and an IR absorbing structure is made in the upper pixel level to cover almost the entire pixel area. The IR absorption utilizes IR reflections from the lower level. Since the reflection from the support leg portions is not perfect due to the slits in the metal reflector, the reflection becomes smaller as the support leg section increases in reduced pixel pitches. In order to achieve high thermal isolation and high IR absorption simultaneously, we have developed a new pixel structure that has an independent IR reflector between the lower and upper levels. The structure assures perfect IR reflection and thus improves IR absorption. The FPA shows a noise equivalent temperature difference (NETD) of 40 mK (f/1.0) and a responsivity non-uniformity of less than 0.9%. The good uniformity is due to the high uniformity of the electrical characteristics of SOI diodes made of single crystal silicon (Si). We have confirmed that the SOI diodes architecture is suitable for large format uncooled IR FPAs.

Method of manufacturing silicon carbide semiconductor device

Abstract: A method of manufacturing a silicon carbide semiconductor device is provided that includes a step of forming in a surface of a silicon carbide wafer of first conductivity type a first region of second conductivity type having a predetermined space thereinside by ion-implanting aluminum as a first impurity and boron as a second impurity; a step of forming a JTE region in the surface of the silicon carbide wafer from the first region by diffusing the boron ion-implanted in the first region toward its neighboring zones by an activation annealing treatment; a step of forming a first electrode on the surface of the silicon carbide wafer at the space inside the first region and at an inner part of the first region; and a step of forming a second electrode on the opposite surface of the silicon carbide wafer Thereby, a JTE region can be formed that has a wide range of impurity concentration and a desired breakdown voltage without increasing the number of steps of the manufacturing process

Concurrent Multiband Digital Outphasing Transmitter Architecture Using Multidimensional Power Coding

Abstract: All-digital outphasing transmitter architecture using multidimensional power coding (MDPC) is proposed for noncontiguous concurrent multiband transmission with a high power efficiency. MDPC transforms multiband digital baseband signals into multibit low-resolution digital signals that drive switching-mode PAs. A prototype digital outphasing transmitter consists of two 1-GHz bandwidth GaN Class-D PAs and a Chireix power combiner. The two GaN PAs are driven by bipolar radio frequency (RF) pulse-width modulation (PWM) signals, which are transformed from a concurrent dual-band LTE signal by MDPC. The dual-band LTE signal with 15-MHz aggregate channel bandwidth at 240 and 500 MHz frequency band is transmitted with $-$ 30 and $-$ 37 dBc out-of-band emissions, respectively. Digital outphasing achieves more than two times higher coding efficiency than conventional concurrent dual-band digital transmitters with the same PAs in Class-S operation. Measured power coding efficiencies of 35.4% and 47.1% are observed with outphasing bipolar and 3-level RF PWM signals respectively, which are encoded from the dual-band LTE signal.