ShengTu Optics
Member
In order to become more familiar with the product and understand the structure of the binocular, we made a special trip to the manufacturer during this period. We received professional training in the factory and learned about the entire assembly process of a binocular, the role of each part, how each part should be installed, etc. We learned a lot! After returning, we disassembled 3 brand new roof binocular, repeatedly disassembled and assembled, and calibrated them. The purpose is to become more familiar with the product, so that we will have a better technical foundation to provide after-sales service in the future. We also took pictures of the entire disassembly and assembly process, and hope that everyone can better understand the binocular through these pictures and this post.
First of all - "peel off the clothes", the surface of the binocular is wrapped with a layer of rubber, which can make it comfortable to hold and non-slip. The rubber and the lens body are glued together.
The same goes for the rubber on the focus hand wheel (if the focus wheel is turned to the bottom and can still turn and slip, it may be that the glue is not adhered well. Other issues will be added later）
The eyepiece can also be removed
The appearance after the "clothes" are stripped off
Then start to remove the eye mask - the eye mask is a screw-on type, with three screws to fix it. There are three grooves on the eye mask, and it can be screwed up along the tracks of these three screws. The screws can be unscrewed with a flat-blade screwdriver and the eye mask can be taken off.
What it looks like after removing the eye mask
Next, I removed the eyepiece. The eyepiece was tightly screwed together with the thread and the lens body. It took a lot of effort to unscrew it. After unscrewing it, I found that there was waterproof glue inside, which can better seal it.
The right eyepiece can be adjusted for parallax. You can see the picture below: By turning the parallax compensation ring, you can see the eyepiece lens moving up and down.
By the way, before we disassemble it, let me introduce the tools we are going to use.
The lens is tightened with a pressure ring. There are two grooves on the pressure ring. You can loosen it with a tool and take out the lens.
After unscrewing, you can see that the eyepiece group is three pieces in two groups.
One of them is two lenses glued together.
Prism part - Before removing the prism, let's insert a paragraph to adjust the three prism fixing screws of the optical axis
There is another hole in the middle of the two screw holes. This hole is for nitrogen filling. Now it is sealed with waterproof glue. Generally, manufacturers will assemble the binocular, fill it with nitrogen, and then seal it with waterproof glue.
After loosening the three prism fixing screws of the binocular, the prism can be taken out. ①②③ in the figure below are the corresponding three screws.
The bottom of the prism is conical, and the three screws can just support the conical part. After tightening, the force is downward, which can fix the prism very stably.
Prism display diagram:
Addendum: The three prism fixing screws are actually covered with waterproof glue, but they were removed when we disassembled them. Usually, the optical axis of the roof binoculars is not straight, which is basically due to the prism being offset. It can be adjusted with three screws. Although the triangle formed by the three screws can make the prism very stable, it is necessary to ensure that the optical axis is parallel. The tightness of the three screws must be controlled when adjusting. This still requires rich experience and an optical axis detector. I personally think it is impossible. Remove the objective lens again.
Gasket inside the objective lens
The objective lens is also composed of two groups of three pieces, one of which is two pieces glued together.
Disassembled objective lens assembly
I have disassembled more than half of it, but I haven't finished it yet. It may seem like not much, but there are actually quite a lot of accessories. Think about it, a pair of glasses, a frame and two lenses cost hundreds of yuan. A pair of binoculars, both sides of the barrel add up to more than a dozen lenses, and they also need to be carefully matched, assembled, coated, etc. A few hundred yuan is really not expensive
Next, let's talk about the focusing mechanism, and then disassemble it: Focusing is generally divided into central focusing and independent focusing (the left and right eyepieces are adjusted separately). For example, binoculars such as the Boguan Thunder 7X50 and the Celestron Celestial 25X100 use independent focusing. Central focusing is divided into internal focusing and external focusing. Among the three roof binoculars we disassembled, one is external focusing. When the focusing wheel is turned, the objective lens moves up and down. This type of mirror is generally not waterproof. There are 2 internal focusing. There is a focusing lens between the objective lens group and the prism. It is connected to the focusing wheel by a brass connecting rod. When the focusing wheel is turned, it can drive the focusing lens to move inside the lens barrel. This internal focusing structure can achieve better sealing and can be nitrogen-filled and waterproof. The eyepiece, prism, and objective lens have all been disassembled, and now there is only the focusing lens left inside.
Start disassembling: Open the cover, and you can see that the surroundings are also glued with waterproof glue. The focus lens is connected to the brass rod, and the brass rod is connected to the focus wheel.
When you turn the focus wheel, you can find that the brass rod drives the focus lenses on both sides to move synchronously to achieve the effect of focusing and adjusting clarity.
