Abstract: A projection device is disposable into a display platform of a display rack having a plurality of display platforms, for directly projecting an image frame onto a projection screen of the display platform. The image frame projected to the projection screen is not reflected by any reflective mirror arranged between the projection device and the projection screen. A length of the image frame in a first direction is equal to at least ten times a length of the image frame in a second direction. Since no reflective mirror is arranged between the projection device and the projection screen, the projection device is more easily applicable to display racks.

Abstract: A display system including a display device and a light combining device is provided. The display device includes a first display region and a second display region. The light combining device has a first surface and a second surface opposite to the first surface. At least one part of a first light beam from the first display region is reflected by the first surface to an observing region so as to form a first virtual image. At least one part of a second light beam from the second display region penetrates through the first surface, is reflected by the second surface, penetrates through the first surface again, and is transmitted to the observing region in sequence, so as to form a second virtual image.

Abstract: A projection lens provided is for projecting an image beam. The projection lens is disposed on a transmission path of the image beam and includes a first group of lenses and a second group of lenses. The first group of lenses includes a first spherical lens and a first aspheric lens. After the image beam passes through the first group of lenses, an intermediate image is formed between the first group of lenses and the second group of lenses, in which the first aspheric lens is the lens in the first group of lenses closest to the second group of lenses. A projection device using the projection lens is also provided. The projection device further includes a planar reflector on the transmission path of the image beam.

Abstract: A power monitoring system includes a power monitoring device and a host. The power monitoring device includes: a plurality of meters, each generating an input detection signal that indicates an electric quantity inputted to a respective load; a detecting unit generating an output detection signal that indicates an electric quantity outputted to a transformer; a processing unit generating, based on the output detection signal and the input detection signals, a state indicator that indicates the presence or absence of energy theft; and a communication unit generating a communication signal that carries the state indicator. The host generates a warning output when the state indicator carried by the communication signal received thereby indicates the presence of energy theft.

Abstract: The invention provides a projection apparatus having an image source, a projection lens, and a beam-splitting module. The image source provides an image beam, and the image beam includes a first sub image beam and at least one second sub image beam. The projection lens is disposed on a transmission path of the image beam. The beam-splitting module projects the first sub image beam passing through the beam-splitting module onto a first imaging plane, and projects the second sub image beam reflected by the beam-splitting module onto at least one second imaging plane. The first imaging plane is not coplanar with the at least one second imaging plane. The projection lens is disposed on the transmission path of the image beam between the beam-splitting module and the image source.

Abstract: An illumination system includes a first light source, a first rotation wheel, a first phosphor element, and a light combining element. The first light source is capable of emitting a first color beam. The first rotation wheel is disposed on a transmission path of the first color beam and includes a first transmissive region and a first reflective region. The first transmissive region is capable of allowing the first color beam to pass through so as to form a first color transmissive beam. The first reflective region is capable of reflecting the first color beam to form a first color reflective beam. One of the first color transmissive and reflective beams excites the first phosphor element to form a second color beam. The light combining element combines the second color beam and a beam originating from the other one of the first color transmissive and reflective beams.

Abstract: A method for locating faults in a power network includes reading power network information stored in a database in a data reading step. A power network matrix is created based on the power network information in a power network creating step. A fault current vector is created in a fault current vector creating step. In a fault locating step, a backward substitution is carried out on the fault current vector and the power network matrix to obtain a detection zone vector, and the fault can be located. The fault locating speed of the power network is, thus, increased.

Abstract: The image projection and capture apparatus for projecting an image beam to display an image on a screen and sensing a sensing beam from the image on the screen, the image projection and capture apparatus includes a light source, a light valve, a projection lens, an image capture lens, a dichroic unit, and an image sensor. The light source provides an illumination beam. The light valve is capable of converting the illumination beam to the image beam. The projection lens has a first optical axis. The image capture lens has a second optical axis. The first optical axis and the second optical axis are collinear. The dichroic unit is disposed between the projection lens and the image capture lens. The image sensor is disposed on a light path of the sensing beam.

Abstract: A light emitting diode (LED) driving circuit suitable for driving an LED load is provided. The LED driving circuit includes an AC voltage source, a bridge rectifier, a plurality of diodes, inductors, transistors and capacitors. The diodes, inductors, transistors and capacitors are configured to form a buck-boost converter and a buck converter, where the buck-boost converter and the buck converter share the transistors as active switches. Designer can design the LED driving circuit with zero-voltage switching-on using the diode characteristic of the existing active switches by selecting suitable circuit parameters.

Abstract: A method for determining a signal transmission mode of a plurality of fault indicators includes a data retrieval step, a mode setting step, a number setting step, an analysis step, a first determination step, a calculation step, a second determination step and a mode number increasing step. Based on the above step, the method is able to determine a preferred number of times the fault signals are required to be transmitted between the plurality of fault indicators when a predetermined transmission success rate is met, reducing the energy consumption and prolonging the service life of the indicators.

Abstract: The invention provides a projection apparatus having an image source, a projection lens, and a beam-splitting module. The image source provides an image beam, and the image beam includes a first sub image beam and at least one second sub image beam. The projection lens is disposed on a transmission path of the image beam. The beam-splitting module projects the first sub image beam passing through the beam-splitting module onto a first imaging plane, and projects the second sub image beam reflected by the beam-splitting module onto at least one second imaging plane. The first imaging plane is not coplanar with the at least one second imaging plane. The projection lens is disposed on the transmission path of the image beam between the beam-splitting module and the image source.

Abstract: An LED driving device includes a DC to DC converter module and a driving module. The DC to DC converter module includes a full-bridge switching circuit for converting a first DC electric power into an AC electric power, a rectifier circuit for converting the AC electric power into a second DC electric power, and a control circuit for modulating pulse phase of the second DC electric power and for controlling switching operation of the full-bridge switching circuit, such that the second DC electric power has a predetermined voltage value. The driving module is operable to receive the second DC electric power, to output a third DC electric power with a predetermined current value for driving an LED module, and to modulate pulse width of the third DC electric power.

Abstract: An LED driving device includes a DC to DC converter module and a driving module. The DC to DC converter module includes a full-bridge switching circuit for converting a first DC electric power into an AC electric power, a rectifier circuit for converting the AC electric power into a second DC electric power, and a control circuit for modulating pulse phase of the second DC electric power and for controlling switching operation of the full-bridge switching circuit, such that the second DC electric power has a predetermined voltage value. The driving module is operable to receive the second DC electric power, to output a third DC electric power with a predetermined current value for driving an LED module, and to modulate pulse width of the third DC electric power.

Abstract: A projection apparatus for projecting a first image and a second image is disclosed. The projection apparatus has a casing, a light source module providing an illumination beam, a light valve device, a first prism, a second prism, a third prism, a fourth prism, a first projection lens, and a second projection lens. The illumination beam enters the first prism, the second prism, the third prism, the fourth prism, and the light valve device. The illumination beam is reflected and converted into a first image beam and a second image beam. The first image beam enters the first prism and is totally reflected to the first projection lens to form the first image. The second image beam enters the third prism and is totally reflected to the second projection lens to form the second image.

Abstract: The disclosure provides a projection device, including an image source, a light-splitting module, and an imaging lens. The image source provides an image beam. The image beam includes a plurality of sub-image beams respectively emitted from a plurality of image areas of the image sources. The light-splitting module has at least one total reflection plane totally reflecting at least one sub-image beam of the sub-image beams and allowing at least another sub-image beam of the sub-image beams to transmit therethrough. The imaging lens includes a rear refractive-element group and a front refractive-element group. The rear and front refractive-element groups are configured on a transmission path of the image beam, and the light-splitting module is configured between the rear and front refractive-element groups.

Abstract: A multi-projection system and a display system using the same are provided. The multi-projection system for projecting a plurality of images included in a beam onto a screen includes a beam source providing the beam; an image splitter in proximity to the beam source and has a positive magnifying ratio; and an imaging device in proximity to the image splitter, wherein the beam passes through the image splitter and the imaging device to be projected onto the screen.

Abstract: A projection lens configured to form an image from an image source which is disposed at an object side is provided. The projection lens includes a lens group and an aspheric mirror. The lens group has a first optical axis, and an intermediate image is formed by the lens group from the image source. The aspheric mirror has a second optical axis and an aspheric surface. The lens group is disposed between the object side and the aspheric mirror. The aspheric surface faces the lens group and reflects the intermediate image to form the image at an image side. The first optical axis is not coaxial with the second optical axis, and an offset of the image relative to the first optical axis is larger than or equal to 100%.

Abstract: A projection lens includes a first image system, a second image system, and a concave reflector arranged in order. The first image system and the second image system define an optical axis, and the concave reflector is disposed at a first side of the optical axis. A projection apparatus using the projection lens is also provided, wherein the first image system is disposed between a light valve of the projection apparatus and the second image system, and the light valve is disposed at the first side of the optical axis.

Abstract: The image projection and capture apparatus for projecting an image beam to display an image on a screen and sensing a sensing beam from the image on the screen, the image projection and capture apparatus includes a light source, a light valve, a projection lens, an image capture lens, a dichroic unit, and an image sensor. The light source provides an illumination beam. The light valve is capable of converting the illumination beam to the image beam. The projection lens has a first optical axis. The image capture lens has a second optical axis. The first optical axis and the second optical axis are collinear. The dichroic unit is disposed between the projection lens and the image capture lens. The image sensor is disposed on a light path of the sensing beam.

Abstract: A monitoring device for an electric power system includes a detection unit and a display unit. The detection unit has a power module, a current detecting module and a transmission module. The power module includes positive and negative electrodes and is coupled to the current detecting module. The current detecting module includes a first switching unit and a second switching unit. The first and second switching units are coupled between the positive and negative electrodes to detect currents on detection points of the electric power system. The transmission module includes a micro-controller unit and a transmission device coupled to the micro-controller unit. The micro-controller unit includes a first end and a second end. The first end is coupled to the first switching unit and the second end is coupled to the second switching unit. The display unit is coupled to the transmission device for receiving signals from the detection unit.