About blackboard reflection what is the reflection of blackboard reflection

The human eye sees the object because the light of the object is reflected to the eye, which is what you call diffuse reflection chaos, such as the blackboard part of the plane is mirror-reflected, then the person in the parallel light path sees the reflection phenomenon, the blackboard will not be particularly flat in a large area in reality, so the parallel beam is very narrow, only a few people are on the specular reflection, others are not in the parallel light path, the large area of high-grade mirrors is reflected by everyone, and if the blackboard has no special plane, everyone sees the brush.

You're thinking wrong. It is supposed to mean that the light source in the classroom is the light emitted by the electric lamp one by one, so some students do the same thing as the part where the reflected light can reach, so they see the reflection, while the other students do not do it in the part where the reflected light can reach, so they do not see the reflection.

No, to be exact, the blackboard reflection belongs to diffuse reflection, but his light reflection has a lot to do with the board surface, the board surface is basically flat, so the vast majority of light is reflected to a certain place, and a few are reflected to other places, this is just a matter of probability size, related to the flatness of the board surface, if it is absolutely flat, it is a specular reflection, and students in other places will not be able to see the blackboard. Got it.

The light is specularly reflected, but there is still a small amount of light, and diffuse reflection occurs.

Blackboard reflection isSpecular reflectionBlackboard reflection means that students in a certain position cannot see the words on the blackboard clearly, and the reason is that the surface of the blackboard is too smooth, and the light is reflected here, and the reflected light is shot out in the same direction, and the students who are in the direction of the reflected light cannot see the words on the blackboard. This illustrates specular reflection and diffuse emission.

Reflection of light. It is divided into specular reflection and diffuse reflection.

When the parallel light hits the surface of the smooth object, the reflected light is still parallel and parallel, and the specular reflection occurs, and when the parallel light hits the uneven surface of the object, the anti-Song Flood ray travels in all directions, and diffuse reflection occurs.

Ways to eliminate blackboard reflections in the classroom:

1. Block the light on the other side of the reflection, which will cause insufficient light when looking at the blackboard.

2. Change the structure of the surface of the blackboard, and replace the previously reflective blackboard with a blackboard with a rough or frosted surface, which has the best effect on solving the blackboard reflection.

3. Try to sit in front of the blackboard and look at the blackboard, and the deviation angle should not be too large.

Introduction to Origins

Before the invention of writing, it was discovered that charcoal could be used for painting, and some ancient murals could be found in some ancient caves in Europe, and the rock walls painted with these murals could already be called blackboards in the traditional sense.

In ancient China, a type of object called a sand table was used in teaching, and hardwood was used to write repeatedly on the sand, but because of the softness of the sand, it could not be considered a blackboard.

In the Middle Ages, lime was mixed with water to make blocks and written on the surface of dark, hard objects in a way similar to a charcoal pen, and in the 19th century, black lacquer was applied to the surface of wooden boards to protect them from erosion, although the main role of blackboards was not to teach at that time, and it was not until the mid-19th century that they became popular in schools around the world.

For more than 200 years, blackboards have evolved from the earliest black paint smeared on hard surfaces such as wood and cement to the terrazzo glass, color-coated steel plates, and composite boards in the 90s. It has witnessed the step-by-step development of the world's education cause, and has made great contributions to the dissemination of knowledge and popularization of education for mankind.

Nowadays, the types of blackboards have also begun to become complex and diverse, and there are blackboards, green boards, and whiteboards in terms of color. From the surface shape, there are flat panels, arc panels, from the structural composition of the bracket movable board, push and pull board, lifting board, magnetic blackboard, from the use of teaching blackboard, office whiteboard, advertising board, display board.

The teaching blackboard has electronic blackboard, multi-functional combination board, combined push-pull blackboard, interactive electronic whiteboard, projection board with screen and so on.

The solutions are, 1, block the light on the other side of the reflection, which will cause insufficient light when looking at the blackboard. 2. Change the structure of the surface of the blackboard, replace the previously reflective blackboard with a blackboard with a rough surface or a frosted surface, this method solves the best blackboard reflective effect 3, try to sit in front of the blackboard to look at the blackboard, and the deviation angle is not too large

If you change to a blackboard with a rough surface, the reflected light will be dispersed, and the reflection of the blackboard will be greatly reduced.

Blackboards are reflective not because the paint isn't "black" enough. Even though something black absorbs most of the light that hits it, there will always be a small part of the light that is reflected.

This is especially true for a very smooth blackboard, where the large, smooth surface reflects a lot of light in the same direction. Although the white characters on the blackboard reflect more light, the rough surface reflects the light dispersibly, and the reflection area of the text is small, so it is still covered by the reflected light of the blackboard and the words on the blackboard cannot be seen clearly.

The blackboard is reflective because of the specular reflection of the glass, just grind it to make it diffuse.

Blackboard reflections are specular reflections. Blackboard reflection means that students in a certain position cannot see the words on the blackboard clearly, the reason is that the surface of the blackboard is too smooth, the light is reflected here, and the reflected light is shot out in the same direction, and the students in the direction of the reflected light cannot see the words on the black wide board. This illustrates specular reflection and diffuse emission.

The reflection of light is divided into specular reflection and diffuse reflection, when the parallel light hits the surface of the object with a smooth surface, the reflected light is still parallel, what happens is specular reflection, when the parallel light hits the uneven surface of the object, the reflected light propagates in all directions, and the silver circle is diffuse.