The objective lens at the forefront of the Leica microscope determines how much information enters the optical system, which we refer to as&# 8217& Flash& Ldquo; Spatial frequency;. Simply put, a lens is a low-pass filter, and if we observe it with the naked eye, the imaging position needs to be clearly visible to the human eye. The close proximity to the naked eye is called NormalNearpoint, which is also known as the focal point in Chinese. For most people, this distance is approximately 25cm.

    The theoretical magnification of an optical microscopy system is 2000 times, corresponding to a resolution of 200nm. The imaging ability of this optical system is equivalent to presenting a limited resolution image of 0.4mm. After an object is microscopic to a certain extent, it has already lost its conventional optical properties.

    If an object is small to a certain extent and its optical properties are poor, it will not be displayed by light, and it will lose its specific shape and color& Flash; The resulting image is a diffraction spot, called Airy disk. This is the scale limit at which a point can accurately image&# 8217& Flash; Abbe limit. When the optical microscope reaches 1500 times, it enters the Abbe limit. This can be said to be the limit of human eye observation. If you continue to work hard, what you need is not a Leica microscope, but an electron microscope.