Complete Guide to Optical Precision Machining Process

 

Optical precision machining is crucial to the creation of modern optics. We use CNC machining in making optical parts. At Cncteck, we offer both 3 -axis and 5- axis CNC machines. Optical parts are increasingly becoming more complex and are thus tasking to process. This comes with the new era of optical precision machining. When it comes to creating non-complex optical parts, there are a few common ways we use them. It entails polishing and normal grinding procedures. However, we can only partially create complex optical parts using these normal methods. This is since they lack dimensional accuracy. In this case, our team of experts opts to use multi-axis machining.

Micro-sized and aspherical optical parts often need very tight tolerances. Precision cutting processes luckily provide this needed accuracy. They achieve this using diamond tools on ultra-precise tools. We thus end up with both a tight tolerance and a high surface finish. We use this method to achieve proper dimensional accuracy for optical parts and their molds. Here is further insight into this.

What Are the Ultra Accurate Production Methods for Optical Parts?

There is one ideal way of fabricating complex micro-optical parts. This is while achieving top-notch surface qualities that reach fractions of a micrometer Ra. It entails using ultraprecise tools along with diamond cutting machines. It takes top-level expertise to attain freeform surfaces, complex geometries, and real 3D parts. We sometimes have to use a few unique methods of multi-axis machining.

There are few methods that machinists employ in optical precision machining. These include laser machining, EDM, grinding, micro-cutting, and silicon etching. Optical machining entails working on planar and freeform optical surfaces. Micro-cutting is the only method that achieves the needed structure size, accuracy, and precision in both optical surfaces.

What Are the Tool Factors for Optical Precision Machining?

Two main factors determine the production quality of the optical parts. These are namely the tool’s cutting-edge roundness and sharpness. We thus have to include special tool geometries. These include ball-endmills, diamond micro-endmills, and other tools for turning and shaping. There are a few of the ultra-precise cutting methods for optical parts. These are namely fly cutting, endmill cutting, plunge cutting, and fast-tool cutting.

Our team of experts sometimes combine vibration-free CNC machines with compact tool holders and fixtures. This allows a single point diamond cutting tool to scrape off material from the workpiece efficiently. The method ensures that a very high and concentrated cutting force acts on the workpiece. We thus end up with few dents elsewhere while keeping perfect form accuracy and surface finish. This enables us to achieve optical precision machining.

What Is Single Point Diamond Tool Turning?

We apply this type of machining when we want to achieve rotationally symmetrical optical parts. It is one of the most efficient cutting processes. This method achieves high cutting speeds and high surface finishes at a Ra of less than 5 nm. The tool we use in this method accounts for the accuracy of the part under production. Our experts often calculate the tool radius along with the compensation for the whole tool during the machining process. Also, we have to take special care when dealing with accuracies in the sub-micron range. This involves controlling the tool’s waviness to a level of 0.1 um of the tool radius. Meanwhile, if we need simpler surface structures, we use plunge cutting with sharp point tools. These methods aid us in achieving optical precision machining.

• Fly-Cutting and CNC Milling

CNC milling is an awesome option when machining intricate surface geometries. We sometimes use it to achieve freeform surface finishes. Examples of optical parts we are able to create include camera lenses, and prototypes for vehicle lighting. In the machining of these parts, we need at least a 3-axis CNC machine.  In contrast, we need a 5-axis machine to obtain accurate optical surface features. There are three major diamond CNC milling tools we use in such a case. These are namely endmills, fly cutting, and ball-endmill tools.

Ball-end mills are vital when dealing with freeform surface features. This is since they can deal with geometries of up to 0.5 mm. Our expert machining services allow us to achieve accuracies of up to R0.1-R0.15 mm for inside corners. Fly-cutting tools are ideal for groove cutting. Moreover, we can use them when working on planar surfaces. For example, we use it to process laser mirrors and pyramid parts.

What Is the Key Role of Optical Precision Machining in the Modern World?

Notably, the need for optical parts is currently at its peak. This comes with a growing consumer market for electronic parts. Of note is the use of camera lenses in DSLRs, smartphones, and scanning mirrors for printers. This comes with a tasking challenge for the market. The main problem is how to cost-effectively produce free-form optical parts. Luckily, precision machining enables us to achieve this. We end up replacing the normal camera lenses with single free-form mirror parts. This allows it to be compact while saving on cost during production.

CNCTECK Precision Engineering Limited is specialized in CNC machining manufacturing, Rapid prototype machining, Low-volume production, Sheet metal fabrication and 3D printing services, we gives you utmost support and quality services. Please kindly send us enquiry now.

In regarding of any questions for metal & plastic technology and customized machining, feel free to contact us below:

Call +86-13476066292 or Send enquiry to us for free quoting.

We are here to support you. Our services email address:

Email: enquiry@cncteck.com