Each spectroscope has its own design features, but they have a common operating principle. The prism-type double-tube spectroscope contains: a collimator with a slit device; prism or diffraction grating; telescope. There is a narrow slit in the focal plane of the lens, the length of which is perpendicular to the plane of the drawing. The slit is illuminated by the beams under investigation. The spectrograph consists of a collimator, a prism, two lenses and a photographic plate. The collimator has a narrow slit through which light enters the device and falls onto the lens in an expanding beam. Since the slit is located in the Local plane of this lens, the light comes out of it in a parallel beam and falls on the prism. Waves of different frequencies (colors) are deflected by the prism at different angles, so parallel beams of different directions emerge from the prism. These beams, refracted in the second lens, form a slit image on the photographic plate located in its focal plane.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.