Conoscope lenses are expensive. Think thousands to tens of thousands of dollars. Before we get into more specifics, please review our page on how much lenses cost in general. Everything on that page applies to conoscopes. Below, you will find information specific to the design and manufacture of conoscopes.
Conoscope lenses typically range from $5,000 to $80,000 or more, depending on design complexity, acceptance angle, resolution requirements, and order quantity. This page breaks down the two main cost drivers — design and manufacturing — with real numbers drawn from Eckhardt projects.
Let’s start with a ballpark design cost estimate: $5k – $30k. The range is wide because conoscopes vary from narrow angle, low resolution models that take fewer than ten lens elements to varifocal, wide angle, high resolution models that can require over twenty. Our most challenging design took about six months to complete, and yes, we way underbid that one. Unless you find a way to surprise us with a requirement unlike any we’ve seen before, that won’t happen again. Typical designs take less than a month.
Things that affect the complexity of the design are similar to most lenses. A larger acceptance angle (field of view) and higher resolution increases complexity and hence cost. Increasing the size of the sample (entrance pupil diameter) also drives up cost because it lowers the F/# of the lens. Both sample size and acceptance angle affect the inherent aberrations of a lens, while higher resolution requires better correction of those aberrations. For more background on this, consult our aberrations page.
A cost driver specific to conoscopes is the working distance, which is the distance between the sample and the front of the conoscope. Especially when the acceptance angle is wide, increasing the working distance quickly drives up the diameter of the lens elements, which increases cost. Yes, this is mostly a manufacturing issue, but it affects the design enough to be worth mentioning here.
If you need more than 50 conoscopes, we will put extra effort into the design to make sure we use as few lens elements as possible and the least expensive types of glass. This takes more time, but the time is amortized over the large quantity, so the total price is lower. At the other end of the range, fewer than ten conoscopes, we consider it important to minimize the design time because the design cost will be a substantial fraction of the total cost.
Quantity is the number one factor in determining the price of a conoscope. There are two aspects to quantity: the number of assemblies you order and the number of lens elements in an assembly. Other factors include element size and glass types, and the difficulty of assembling the lens. Lens elements for conoscopes are rarely less than 1 cm diameter and can grow to 10cm. BK7 is the least expensive optical glass; in raw strips, it costs about $30/kg. We avoid glasses that cost more than 12 times as much as BK7.
The cost related to the number of elements, their size, and their glass type do not change with order quantity; however, the cost related to difficulty does. That’s because of the learning curve: every additional lens we make is a little easier than the last one due to the learning that takes place during the assembly process.
Let’s talk about the number of assembled conoscopes you order, specifically at the low end. It is common for the lens elements for two assemblies to cost only 20% more than one, although the mechanical costs and assembly time almost double. The net effect is that two assemblies will typically cost only 30% more than one. Unfortunately, buying a second assembly later will necessitate a second production run, which will cost as much as the first one. For this reason, unless you are absolutely certain you will never need a second, it’s wise to purchase two.
Assembling a single complex conoscope can take forty hours for the first sample. Our cost estimates are based on $100/hour. This is not because that’s what we pay our technicians; it’s because engineers are often involved in the assembly of the first few samples. This is partially because we want them to be painfully aware of any design mistakes, but mostly because they have a deep knowledge of the design which can be helpful in the assembly process. With experience, a fairly complicated conoscope can be assembled in a few hours.
Illustrative estimates only. Actual costs depend on your acceptance angle, resolution, working distance, sample size, and order quantity. Design cost is shared across all units in the same order.
Every conoscope we design starts with a conversation. Share your key parameters and we’ll give you a realistic cost range before any commitment.