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Just like the arcade machine, the switch is turned on when the coin is flipped, and the timer will be turned off when it is then.
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A refracting telescope is a system that uses lenticular crop mirrors to concentrate light. The world's first astronomical telescope was a refracting telescope made by Galileo, which used a convex lens as its objective. Due to the different refractive indices of glass to different colors of light, refracting telescopes will produce serious chromatic aberration, therefore, later refracting telescopes mostly use compound lenses as objective lenses, that is, composed of more than two lenses, to eliminate chromatic aberration (such as the ED series of Meade company in the United States).
Depending on the optical path, there are two types of refracting telescopes: the Galilean telescope and the Kepler telescope. Generally, refracting telescopes have a small relative aperture, that is, a long focal length and a large negative scale, so that the resolution is high, which is more suitable for astrometric work (such as measuring the position of stars, the angular distance of double stars, etc.).
Advantages: easy to use and simple to manufacture.
Ideal for observing moons, planets, binary stars, and especially for telescopes with large apertures.
Compact and requires no additional maintenance.
The closed barrel attenuates the damage to image quality caused by air flow while protecting the optical lens.
Easy to carry and suitable for long-distance outdoor observation.
Secondary imaging can be avoided and a high-contrast image quality can be formed.
Through the achromatic design, the appearance of color aberration can be well avoided.
Cons: More expensive than Newtonian or Casseille.
At the same aperture, refracting telescopes are heavier, longer, and larger than Newtonian or Cassegreen telescopes.
Due to the limitation of aperture, it is not suitable for observing deep-sky objects such as extragalactic galaxies, nebulae, etc.
The disadvantage of the small focal point makes it difficult to photograph deep-sky objects with refracting telescopes.
In the achromatic design, the color of the resulting image will be more or less distorted.
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Coin-operated telescopes are also known as coin-operated telescopes, and a standard coin-operated telescope should have 30x magnification to meet the high magnification requirements of consumers. Conventional coin-operated telescopes are below 20x, but the latest optical technology has increased magnification to 30x, making images clearer, brighter, and with a clear view of the moon's surface potholes.
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The diameter of the mouth fluid buried in the coin telescope is generally 80mm, and the diameter of the objective lens is 80mm, so that the light collection effect is better, and the image is clearer and brighter at night. In addition, a standard coin-operated telescope mirror should also be waterproof and anti-oxidation, and can be placed indoors and outdoors.
I'm an incompetent astronomy fan, so let me explain your problem briefly. The main reasons why telescopes can see distant objects clearly are the following points: light gathering ability, magnification, and resolution. The reason why we see the change of light and shade of the object is mainly determined by the amount of photons entering the optic nerve in the region, so to observe the darker object, this requires a stronger light-gathering ability to enhance the amount of photons in the area, which requires a large-diameter lens (in the lens ignition paper experiment, it can be clearly seen that there are multiple light areas in the sun, the sunlight on the ground outside the lens, the shadow of the lens and the spotlight, you can find that the shadow of the lens is much darker than the sunlight on the ground outside, The spot is much brighter than the sunlight on the ground outside, which means that the lens concentrates the photons on the lens to the ** area, so the unexpected area is darkened due to the decrease in the amount of photons, so that the larger the mirror diameter, the more photons in the ** area, and the greater the energy). >>>More
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Chemistry Basics. You have to know that chemistry is still the basic origin of life. >>>More
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A stepper motor is an actuator that converts electrical impulses into angular displacement. When the stepper driver receives a pulse signal, it drives the stepper motor to rotate at a fixed angle (called the "step angle") in a set direction, and its rotation is to run step by step at a fixed angle. The angular displacement can be controlled by controlling the number of pulses, so as to achieve the purpose of accurate positioning; At the same time, the speed and acceleration of the motor can be controlled by controlling the pulse frequency, so as to achieve the purpose of speed regulation. >>>More
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