Projection equipment for aided teaching

Abstract

The invention discloses projection equipment for aided teaching. The projection equipment comprises a projector, a fixing base is arranged on the right side of the projector, the inner wall of the fixing base and the outer wall of the projector are in overlapping connection, an inner rod is installed on the inner wall of the fixing base, the outer wall of the inner rod and the outer wall of the fixing base are in overlapping connection, an outer rod is arranged on the outer wall of the inner rod, a sliding plate is installed on the inner wall of the outer rod, and the outer wall of the slidingplate and the inner wall of the outer rod are in overlapping connection. According to the projection equipment, through cooperation of a fixing ring, the inner rod and the outer rod under the actionof the fixing base, the problems that the cost of purchasing teaching aids of a school is increased and projection equipment easily causes the work fatigue of instructors and maintenance workers in the use are avoided, the efficiency of learning and use of teachers and students is improved, the work fatigue of the teachers during the lectures is avoided, the use expenses of purchasing teaching aids are saved, the waste of the teaching aids is avoided, and the projection equipment is suitable for popularization and use.

Description

technical field [0001] The invention relates to the technical field of teaching aids, in particular to a projection device for auxiliary teaching. Background technique [0002] So far, relatively advanced projectors that are widely used in teaching, conferences, and demonstrations are mainly realized through three display technologies, namely, CRT (cathode ray tube) projection technology, LCD (liquid crystal display) projection technology, and recently developed projectors. CRT is the abbreviation of English Cathode Ray Tube, translated as cathode ray tube. As an imaging device, it is the earliest and most widely used display technology. This kind of projector can decompose the input signal source into three colors of R (red), G (green) and B (blue) and project them to the CRT tube. On the fluorescent screen, the fluorescent powder is enlarged and converged by the light-emitting system under high pressure, and a color image is displayed on the screen. This kind of projector...

AI Technical Summary

Problems solved by technology

The optical signal output by the CRT is irradiated on the photoelectric converter, and the optical signal is converted into a continuously changing electrical signal: an external light source generates a beam of strong light, which is projected on the liquid crystal light valve, reflected by the internal mirror, and passed through the optical modulator. Changing its optical characteristics, the polarizing filter following the light valve will filter out the light in other directions, and only allow the light in the same direction as its optical slit to pass through. This light is recombined with the CRT signal and projected onto the large screen. It is the projector with the highest brightness and resolution so far, with a brightness of up to 6000 lumens and a resolution of 2500×2000. It is suitable for occasions with strong ambient light and many audiences, such as super-large-scale command centers, conference centers and large-scale entertainment The location, but its price is high, the volume is large, and the light valve is not easy to maintain. The main brands are: Hughes-JVC, Ampro, etc. The imaging device of the liquid crystal panel projector is a liquid crystal panel, which is also a passive projection method, using an external light source Metal halide lamp or UHP (cold light source), if it is designed with three LCD panels, the strong light will pass through the beam splitter to form three RGB (red, green and blue) beams of light, which are respectively transmitted through the RGB three-color LCD panel: the signal source is converted from analog to digital , the modulation is added to the liquid crystal panel to control the opening and closing of the liquid crystal unit, thereby controlling the on or off of the optical path, and then the light is combined by the mirror, enlarged by the optical lens, and displayed on the large screen. Single-chip design is popular in school (LCD single board, light does not need to be separated), this kind of projector is small in size, light in weight, easy to operate and carry, but its light source life is short, the color is not very uniform, and the resolution is low

The highest resolution is 1024×768, and it is mostly used for temporary demonstrations or small meetings. Although this kind of projector also realizes digital modulation signals, the physical characteristics of the liquid crystal itself determine its slow response speed. One of the inherent shortcomings of LCD technology is the loss of brightness

Since the LCD panel is covered with a grid, it will block the light from passing through. The problem is especially serious at high resolution, and even 60% of the light will be lost, which seriously affects the brightness performance of the LCD projector.

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