Abstract: A method for manufacturing a photoacoustic ultrasound generator includes forming an uncured prepolymer polydimethylsiloxane (PDMS) film on a substrate, spraying a solution of light-absorbing nano-particles onto a surface of the uncured PDMS film, and then permeating and diffusing the light-absorbing nano-particles into the uncured PDMS film; and curing the uncured PDMS film containing the light-absorbing nano-particles distributed therein to form a composite film of nano-particles and PDMS.

Abstract: An embodiment relates to an optical polyester film. The optical polyester film according to one embodiment can minimize the difference between the orientation angle at the center and the orientation angle at the end of the film while producing a difference between the tensile strengths in the lengthwise/widthwise directions of the film, thereby increasing mechanical strength and brightness and suppressing the occurrence of polarization Mura defects. Further, the optical polyester film employs a single layer film, and thus is more easily processed and has a slimmer thickness. Therefore, the optical polyester film can be usefully applied to small-sized thin film display devices and, specifically, can be favorably used as a substrate material of a prism sheet or a polarized reflection sheet.

Abstract: The polyester film according to an embodiment has a coefficient of determination (R2) of the strain with respect to stress and a crystallinity adjusted to specific ranges, whereby it is possible to achieve the flexibility that does not cause deformation even when a certain stress is sustained for a long period of time and the resistant characteristics to the impact of external pressing. Accordingly, the polyester film can be applied to a cover of a flexible display device, in particular, a foldable display device to exhibit excellent characteristics.

Abstract: The optical multilayer film, which comprises a laminate in which a base layer, a primer layer, a hard coat layer, a first refractive layer, and a second refractive layer are sequentially laminated, has a very low reflectance and enhanced optical characteristics by adjusting the in-plane retardation of the base layer and the refractive indices of the respective layers. Thus, the optical component and the display device, which comprise the optical multilayer film, have a low reflectance and excellent other optical characteristics.

Abstract: A battery condition monitoring apparatus includes a measurer configured to measure a charging current which is an internal current of a converter and is charged into a sub-battery, a charging voltage of the converter, and an ambient temperature of a vehicle, an impedance calculator configured to an impedance of the sub-battery on basis of a voltage and a current each measured by the measurer, and a determiner configured to determine a condition of the sub-battery by using the ambient temperature of the vehicle and the impedance of the sub-battery.

Abstract: In the polyester film according to an embodiment, the strain with respect to tensile load and the crystallinity are adjusted to specific ranges, whereby it is possible to achieve the flexibility that does not cause deformation even when a certain load is sustained for a long period of time and the resistant characteristics to the impact of external pressing. Accordingly, the polyester film can be applied to a cover of a flexible display device, in particular, a foldable display device to exhibit excellent characteristics.

Abstract: The polyester film according to the embodiment achieves the elasticity required for a cover of a flexible display by increasing the rate of increase in stress in an initial stage of strain to a certain level or higher. As a result, it is possible to maintain the original characteristics when it is applied to a cover of a flexible display device and subjected to a plurality of repeated folding. Accordingly, the polyester film can be applied to a cover of a flexible display device, in particular, a foldable display device to exhibit excellent characteristics.

Abstract: The present disclosure relates to a polyester resin composition including a polyester resin including a diol residue and a dicarboxylic acid residue, wherein the diol residue includes a cyclohexanedimethanol residue and the dicarboxylic acid residue includes an isophthalic acid residue and a terephthalic acid residue, wherein an amount of the isophthalic acid residue is 0 to 20 mol % when a total amount of the dicarboxylic acid residue is considered as 100 mol %, wherein an amount of the cyclohexanedimethanol residue is 50 to 100 mol % when a total amount of the diol residue is considered as 100 mol %, wherein the polyester resin composition includes an antioxidant, and wherein the antioxidant includes a phenol-based antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant.

Abstract: The tissue removal device using focused ultrasound includes a focused ultrasound output unit, a mode setting unit to set an output mode of the focused ultrasound, and a control unit to control output characteristics of the focused ultrasound according to the set mode, wherein the output mode is selected from a first mode for removing a tissue in a local area using a vapor bubble formed by the focused ultrasound, a second mode for removing a tissue in a narrower area than the first mode by controlling the output characteristics of the focused ultrasound immediately after the vapor bubble is formed by the focused ultrasound, and a third mode for obtaining a skin tightening effect by generating heating in a subcutaneous fat layer using focused ultrasound of lower intensity and a longer pulse length than the first mode and the second mode.

Abstract: A film for an electronic board, according to one embodiment, has a low dielectric constant of 2.9 or lower at a frequency of 10-40 GHz, and thus can cause the signal transmission rate for a high frequency use, such as fifth generation (5G) mobile communication, to be superior to that of a conventional film for an electronic board. In addition, the film for an electronic board has flexibility and physicochemical characteristics that are greater than or equal to those of a conventional film, so as to be applicable to the manufacture of a laminate of a conductive film such as FCCL and an electronic board such as a FPCB, thereby enabling processability, durability, transmission capacity and the like to be improved.

Abstract: A film for an electronic substrate according to an embodiment has a moisture-absorption rate of less than 0.3% of the initial weight when immersed in water for 24 hours, and thus is less susceptible than existing films for electronic substrates are to changes in dimension or degradation in electrical characteristics caused by containing moisture according to changes in temperature and humidity. Also, the film for an electronic substrate is equal or superior to existing films in terms of flexibility and physicochemical characteristics, and thus may be applied to the manufacture of laminates with a conductive film such as FCCL and electronic substrates such as FPCB to improve processability, durability, transmission capacity, etc.

Abstract: The optical multilayer film, which comprises a laminate in which a base layer, a primer layer, and a hard coat layer are sequentially laminated, has enhanced mechanical properties while preventing rainbow stains and a reduction in the visibility by adjusting the in-plane retardation of the base layer and the refractive indices of the respective layers. Thus, the optical component and the display device, which comprise the optical multilayer film, have excellent optical characteristics and can operate normally even in harsh environments.

Abstract: A protection film according to an embodiment implements a very low reflectivity through a multilayer structure of which the refractive index is controlled and does not cause whitening and cracking to occur even in the case of frequent bending or folding thereof. Accordingly, the protection film is applied to a flexible display device, and especially to a cover of a foldable display device, thereby showing excellent optical and mechanical characteristics.

Abstract: A Low-voltage DC-DC Converter (LDC) includes a new bidirectional isolated LDC, in which two converters with different power circuit topologies operate in parallel in order to enable both buck mode and boost mode. The two applied converters are a phase-shift full-bridge converter with full-bridge synchronous rectification and an active-clamp forward converter. According to the present invention, it is possible to achieve the advantages of both a phase-shifted full-bridge converter with full-bridge synchronous rectification applied and an active clamping forward converter. Thus, it is possible to minimize output voltage and current ripples, thereby improving the quality of the LDC output power while minimizing electromagnetic waves generated while a product is operating.

Abstract: Provided is a new LDC to satisfy the recent requirements for a bidirectional large-capacity isolated LDC (DC-DC converter). The present disclosure provides a new bidirectional isolated LDC, in which two converters with different power circuit topologies operate in parallel in order to enable both buck mode and boost mode. The two applied converters are a phase-shift full-bridge converter with full-bridge synchronous rectification and an active-clamp forward converter. According to the present invention, it is possible to achieve the advantages of both a phase-shifted full-bridge converter with full-bridge synchronous rectification applied and an active clamping forward converter. Thus, it is to possible to minimize output voltage and current ripples, thereby improving the quality of the LDC output power while minimizing electromagnetic waves generated while a product is operating.

Abstract: Embodiments relate to an optical film and a liquid crystal display device comprising the same. More specifically, the embodiments relate to an optical film that is excellent in optical characteristics and has no polarization unevenness since it comprises a base layer that has a low in-plane retardation and a low thickness direction retardation and has an excellent adhesiveness by virtue of a proper level of surface tension, a process for preparing the same, and a liquid crystal display device comprising the same.

Abstract: The bidirectional insulating DC-DC converter shares high/low voltage terminals, a cooling passage, a housing, and a control board, and two independent step-down circuit (10) and step-up circuit (20) are formed in parallel to perform a bidirectional DC power conversion. A high voltage applied from a high voltage battery HV is stepped down through the step-down circuit (10) and output to a low voltage battery LV. On the other hand, a low voltage applied from the low voltage battery LV is stepped up through the step-up circuit (20) and output to the high voltage battery HV. The step-down circuit (10) is formed as an active clamp forward converter circuit, and the step-up circuit (20) is formed as an active clamp flyback converter circuit.

Abstract: The present disclosure relates to a new bidirectional low voltage DC-DC converter (LDC), that is, a DC-DC converter capable of satisfying a safety level required for an eco-friendly vehicle and an autonomous vehicle and improving power conversion performance, and a method and an apparatus for controlling the same. The LDC proposed in the present disclosure is a new concept bidirectional LDC in which a plurality of converters having the same power circuit topology are subjected to a parallel interleaving operation so as to enable both a buck operation and a boost operation, satisfy a high safety level, and improve power conversion performance. To this end, a plurality of bidirectional active-clamp flyback converters (for example, two or more bidirectional active-clamp flyback converters) are connected in parallel and are interleaved and controlled by a controller (for example, a microcomputer).

Abstract: The present disclosure is for minimizing the parasitic resistance of an output capacitor of a low-voltage DC-DC converter (LDC) proposed to improve a lifespan of a battery and increase efficiency of the DC-DC converter through reduction of an equivalent series resistance (ESR) of an output capacitor in an N-phase interleaving type vehicle DC-DC converter. According to the present disclosure, the LDC includes: an N-phase power circuit configured by connection of N DC-DC converters in parallel between a high-voltage (HV) battery and a low-voltage (LV) battery; and one output capacitor commonly connected to an output of each phase DC-DC converter, wherein each phase of the N-phase power circuit is controlled in an interleaving manner which delays a phase by 360°/N. Here, each N-phase power circuit is controlled by switching at a frequency of [(a frequency at which the parasitic resistance (equivalent series resistance (ESR)) of the output capacitor is minimized)/N].

Abstract: An aspect of the present disclosure provides a bus bar as a winding in a core of a transformer includes multiple sub-bars arranged horizontally and connected in parallel so as to minimize an AC current in the transformer, and the sub-bars have different widths and thus resistances or impedances with respect to a current flowing through the sub-bars are the same. Another aspect of the present disclosure provides a method of designing a bus bar for resistance or impedance matching between multiple sub-bars included in the bus bar to share a current to minimize an AC current in the transformer. Another aspect of the present disclosure provides a transformer, for a DC-DC converter for use in a vehicle, which is manufactured by the method of designing a bus bar.