LBP Optics diamond machining facility creates bespoke precision engineered components. Most of our products fall in to the categories below:
Cold shields are used to protect image sensors from stray radiation particularly in the 8-13 micron wavelength range. They are commonly used at cryogenic temperatures which increases the signal to noise ratio in thermal imaging systems. To enhance the system performance still further cold shields are often gold coated and can reflect 99% of infrared energy. They were originally used by the military in the late seventies.
Since diamond machined aluminium cold shields can be machined to a highly reflective surface with integral mounting and location points, they are a cost effective and lightweight solution to enhance the performance of infrared systems.
These are components that have two different radii at 90 degrees to each other and are often used to correct astigmatism. They can be machined by rotating the component the required distance from the axis of rotation. The second radius is then machined at right angles to it. If these radii are too large it becomes impractical to swing the component at the required distance from the centre of rotation.
This group of components are machined by rotating the diamond tool at a precise radius at high speed. The component is then moved at an angle through the rotating tool path. This is known as R-theta fly cutting.
The resulting surface produces two foci along the optical path. This is often used to produce a “virtual image” or move the position of a focus.
LBP Optics have been manufacturing aspheric lenses, mirrors and moulds for many years, including ellipsoids, parabolas and hyperbolas. We use the best single crystal diamonds. These tools are manufactured and inspected to ensure that they have a cutting edge roundness of less than 30nm.
Single point diamond turning is ideally suited to this rotationally symmetrical surface form for aspheric lenses, mirrors and moulds. Because diamond machined aspheric optics do not suffer the spherical aberrations found in traditionally polished spherical optics, this allows optical designers to reduce the number of elements needed in an optical system. Aspheric optics are increasingly being used in all facets of the photonics industry including camera phones and contact lenses.
There are many advantages in diamond machined aspheric optical elements:
- The performance of optical systems is greatly increased.
- The number of elements can be reduced within an optical system.
- <2nm integral optical alignment surfaces are possible.
Cylindrical, Conic, Bores & Tapers
These geometric shapes are ideally suited to single point diamond turning. The machining configuration for these types of components is similar to a standard lathe. However, our diamond machines can machine to unparalleled accuracies. Our slide ways have a straightness of better than 200nm over the full travel. The air bearing spindles have an axial and radial accuracy of better than 12nm. The CNC feedback resolution is 0.034nm.
These ultra accurate machines, along with the many years of diamond machining experience our engineers have, enable LBP Optics to supply some of the most accurate components available.
In today’s digital world the need for high speed rotating and oscillating scanning optics is ever increasing. The use of lightweight materials in these optical systems, such as aluminium, is fundamental.
We have been manufacturing these parts for over 20 years and can achieve s urface figure errors of less than 30nm rms.
If the correct substrate material is chosen surface finishes of as little as 20nm rms can be maintained, which results in minimal surface scatter.
The optical performance of these systems also relies on the mechanical dimensional tolerances. So we work closely with customers to make sure that the optical design incorporates diamond machined reference faces, diameters and bores.
The optical engineers at LBP Optics have been diamond machining high precision flat surfaces for more than 20 years, after developing the process for diamond machining 14” aluminium hard disk drives. We can machine plano mirror surfaces from Ø1mm to Ø500mm. Our expertise and experience has enabled us to develop processes to machine thin (0.30mm thick) mirrors flat to a few wavelengths. We have machined 2mm thick mirrors flat to λ/10 each side with a surface finish of 2.5nm rms.
Not all of these precise flat surfaces are used as optical components. We regularly machine panels 700mm x 150mm x 2mm thick from 99.999% pure aluminium to a surface finish of 10nm rms. These surfaces are used to grow in an organic membrane used in the medical industry. Because of our ability to machine up to Ø500mm we are able tocan provide our customers with lightweight precision plates on which to mount their optical assemblies and test fixtures.