What is a Lenticular?

A lenticular lens is a type of lenticular lens sheet. The lenticular lens sheet includes an entrance surface and an exit surface. The lenticular lens sheet is characterized in that the focal length of the middle portion of the lens surface is long and the focal length of the end portion of each lens surface is short. The lenticular lens is mainly used for focusing light from a point light source or transmitting images to other optical systems.

A lenticular lens is a type of lenticular lens sheet.

Lens base point position and focal length:

The focal length of the known objective lens is

, The focal length of the eyepiece is

The distance between the objective lens and the eyepiece is set to L. For simplicity, for the first imaging, the object distance is set to

In order to ensure that the primary image is a magnified real image,

Satisfy

, By the convex lens imaging formula

It can be obtained that the image distance of the first imaging is

, The magnification of the first imaging

, Serving as a magnified inverted real image

. In the following, when the distance L between the objective lens and the eyepiece takes different values, the total magnification of the system and the situation of the final imaging position are analyzed.

(1) When first imaging

Located on the right side of the eyepiece, that is, when L <v ₁ , the object distance of the second imaging is:

As shown in the figure, similarity can be obtained from triangles

.

The magnification of the second imaging is:

The total magnification of a lenticular lens microscope system is the product of two magnifications, namely:

The second imaging position is at:

From this, it can be seen that the object becomes an enlarged image through the objective lens, and then a reduced image through the eyepiece. In this case, the total magnification of the system can be greater than 1 or less than 1, which is not suitable for designing a microscope with a large magnification.

(2) When the first imaging is located on the left side of the eyepiece and the distance from the eyepiece is less than one focal length, that is,

.

The total magnification of the microscope system:

The imaging position is at:

The second imaging is located on the left side of the eyepiece. As shown in the figure, a real image of an inverted magnification is finally formed on the left side of the eyepiece. This kind of tube length is the case of ordinary microscope imaging, and microscope experiments can be designed in this tube length range.

(3) When the length of the lens barrel continues to increase, making the first imaging on the left side of the eyepiece, and the distance from the eyepiece is greater than one focal length and less than twice the focal length, that is

The total magnification of the microscope system:

The imaging position is at:

The second imaging is to the right of the eyepiece. As shown in the figure, a real image of an inverted magnification is finally formed on the right side of the eyepiece. In this case, placing a white screen at the imaging position can receive a real image of the object upright. Therefore, in this case, the convex lens system also achieves two magnifications, which can be used to design an orthophoto microscope.

(4) Increase the lens barrel length again.

That is, when the first imaging is on the left side of the eyepiece and the distance from the eyepiece is greater than twice the focal length:

Magnification of the microscope system:

Its value may be less than 1 or greater than 1. The imaging position is:

v ₂ is positive and the second imaging is on the right side of the eyepiece. As shown in the figure, the first time becomes an enlarged image, and the second time becomes a reduced image. This tube length range is also not suitable for designing microscopes. ^[3-4]