How does the periscope camera work?

TL;DR: Periscope cameras use a prism/mirror combo to reflect light 90 degrees and send it through lens elements onto the sensor. It’s used for magnification purposes.

If you can stomach a teardown of the iPhone 15 Pro Max when it becomes available, you’ll get to see what’s so special about a periscope camera: first of all, often it has a rectangular front element (which you can see even without the device being disassembled), unlike the other cameras (they’re circular). The iPhone 15 Pro Max, however, features a circular front element lens, not a rectangular. Very exotic.


In the periscope camera unit there’s a prism (or angled mirror) that reflects and redirects the light to the side. The light travels through the adjacent lens element and finally hits the sensor. Note that because of the orientation of the elements, the sensor is placed perpendicularly to the phone's back instead of in parallel. Think of it like that: if the ‘regular’ sensors face away from the back, the periscope one is facing the side buttons. Again, as with the rectangular front element of the lens, on the iPhone 15 Pro Max that's not the case and the sensor is indeed in parallel.

Of course, nothing is perfect and there are downsides. Yes, the periscope array is used in the name of compactness, but that’s in terms of ‘thickness’. This exotic camera uses a lot of inner space, just sideways, so in a smaller phone, some components and features ultimately have to be moved or removed in order to make room for the periscope. There are also possible issues like blurring and darkening the image because of the periscope optical scheme, but technology is advancing fast enough to minimize these problems.

Notable models with periscope cameras

Before we talk about some notable phone models putting in use the periscope camera system, as promised, here are the optical zoom monsters with protruding camera-like zoom lenses. Since you don’t see that design at all these days, you can safely assume they didn’t perform well at all (at least in US and Europe) in terms of sales and popularity. We’re talking about Samsung’s Galaxy K Zoom and the Galaxy S4 Zoom. Both devices offered 10x optical zoom lenses (24-240mm in terms of standard 35mm equivalent), xenon flashes, optical image stabilization and Samsung glass. Different sensors were put in the two devices, so there was a difference in the megapixel count: 16 vs 20.7 megapixels total.

The first mainstream device to embody a periscope camera is Huawei’s P30 Pro (2019), which brought to the table remarkable zoom capabilities. However, some remember the ancient times, and specifically 2004, when the Sharp 902 phone (which had 2x optical zoom) appeared and the internet claims it was the first mobile phone to incorporate a periscope technology in its camera setup. That’s impressive, given that the first camera phone had hit the market only a few years earlier.

Today the landscape is filled with periscopes. One can choose between Samsung Galaxy S23 Ultra (or the S22 Ultra, for that matter), Google Pixel 7 Pro (or the Pixel 6 Pro), Honor Magic5 Pro, OPPO Find X6 Pro and others.

And now, you get one in Apple’s newest maxed-out flagship: the iPhone 15 Pro Max. Choose wisely!