Host:

Great. So, as I had mentioned, umm the IMX415, the IMX715, and the IMX678 all deliver similar imaging output. I guess my first question would be, why does the choice between them matter at all?!

Speaker:

Fair enough. The quick answer is, “It doesn't matter”. Ironically, the resolution being identical is actually what makes this comparison easy to get wrong. All three output 4K Ultra-HD at 3840 by 2160 and support RAW10 and RAW12. But where they genuinely differ is in how they handle low-light conditions and high dynamic range scenes. Broadly, that is what determines which sensor is the right fit for a given application.

Host:

So what is driving that performance difference between them?

Speaker:

Uhmm, basically, it's about the sensor platform they are built on. The IMX415 and IMX715 belong to Sony's STARVIS generation. The IMX678 is based on STARVIS 2. That generational distinction is the root of almost every meaningful difference between them.

Host:

Can you explain what STARVIS and STARVIS 2 each bring to the table?

Speaker:

STARVIS uses a back-side-illuminated architecture, referred to as BSI. In this design, the wiring is placed behind the photodiode, which allows more light to reach the photon-collecting area directly. It results in higher quantum efficiency and improved sensitivity across visible and near-infrared wavelengths.

STARVIS 2 retains the BSI architecture and introduces deep trench isolation (DTI). This further improves sensitivity and dynamic range by optimizing the photodiode structures and charge conversion efficiency.

The IMX678 is the sensor in this comparison that is based on STARVIS 2.

Host:

Now, let's talk about the IMX415. How does it position itself in this comparison?

Speaker:

The IMX415 was Sony's flagship 8MP sensor in the 1/2.8-inch format, targeting surveillance and industrial markets. It has a 1.45 micrometer pixel pitch and is designed for compact optical setups with small-format lenses. It is the only one of the three available in color and monochrome variants.

Host:

And how does the IMX715 take things forward from there?

Speaker:

Right. So the IMX715 remains within the STARVIS generation and retains the identical 1/2.8-inch format and 1.45 micrometer pixel pitch. The improvement is specifically in near-infrared sensitivity, achieved through refined BSI pixel processing within the STARVIS architecture. For applications using infrared illumination at 850 nm or 940 nm in low-light environments, that improvement can make a big difference.

Host:

I see. The IMX678 is clearly a more substantial step forward. What makes it different, though?

Speaker:

The IMX678 uses a larger 1/1.8-inch sensor format with a 2.0 micrometer pixel pitch. That represents nearly 90% more pixel area compared to the 1.45 micrometer sensors. On top of that, STARVIS 2 delivers a dynamic range advantage exceeding 8 dB over STARVIS for the same pixel size in a single exposure.

Host:

The HDR capabilities differ across these three as well. Can you take us through those?

Speaker:

HDR is critical in surveillance and industrial settings where a single frame often captures both brightly lit and deeply shadowed areas simultaneously. All three sensors support Digital Overlap HDR, DOL-HDR, which embeds long and short exposures within the separate readout, reducing motion artifacts compared to frame-sequential HDR methods.

The IMX415 and IMX715 also support multiple exposure HDR, which offers more flexibility in controlling exposure ratios.

The IMX678 introduces Clear HDR, which is exclusive to STARVIS 2. This mode extends dynamic range within a single exposure, which eliminates the ghosting and motion blur that multi-exposure approaches can introduce.

A practical example is a moving number plate. In Clear HDR, the plate is captured sharply with no motion artifact. In DOL-HDR under the same conditions, motion artifact is visible.

Host:

Mm-hmm. So a single exposure is doing the job of several.

Speaker:

Yep. That is the foundation of what Clear HDR delivers.

Host:

How does the larger sensor format of the IMX678 affect frame rate?

Speaker:

Yeah, so the IMX415 and IMX715 both reach 90.9 fps at 10-bit and 60.3 fps at 12-bit in all-pixel scan mode. The IMX678 operates at 72 fps at 10-bit and 60 fps at 12-bit. The larger sensor format requires higher pixel data bandwidth, which accounts for the difference in frame rate.

Host:

And how do the output interfaces compare?

Speaker:

All three use CSI-2 as the primary output interface. The IMX415 and IMX715 support 2-lane and 4-lane configurations. The IMX678 additionally supports 8-lane and dual 4-lane by 2-channel configurations, which provide greater flexibility for system designs with higher bandwidth requirements.

All three sensors also support 2x2 pixel binning, which reduces the output resolution to 1920 by 1080. In this mode, neighboring pixels are averaged into a single sample, quadrupling the light-gathering area at the cost of spatial resolution.

This is a useful option in very dark scenes, and importantly, each sensor maintains its maximum frame rate in binning mode.

Host:

Ahhh ok. I suppose the larger format of the IMX678 also changes the lens requirement. Now, what does this mean for a system designer?

Speaker:

The IMX415 and IMX715, with their 6.4mm diagonal and 1/2.8-inch format, are compatible with compact cameras using small-format lenses. The IMX678, with an 8.86mm diagonal, requires a lens with a larger image circle. The advantages are the ability to resolve fine details across the field of view, better low-light focus, sharper NIR imaging, and reduced sensitivity to chromatic aberration.

Host:

And on near-infrared performance specifically, how do the three differ?

Speaker:

So the IMX715 improved NIR sensitivity over earlier STARVIS sensors through refined BSI pixel processing. The IMX678 enhances NIR performance through a deeper photodiode structure that reduces NIR absorption losses. That is an architectural improvement that comes from the STARVIS 2 platform rather than a refinement within the same generation.

Host:

Mm-hmm. Putting all of this together, how would you guide someone who is trying to decide between the three?

Speaker:

The decision comes down to system constraints, lighting conditions, and optical requirements.

The IMX415 is a cost-effective option for standard surveillance applications where a compact form factor is the priority.

The IMX715 is the right choice when improved NIR sensitivity within that same compact format is what the application demands, such as smart city deployments or parking lot management.

The IMX678 is suited to applications where sensitivity and dynamic range are the defining requirements, including low-light AI vision systems, traffic monitoring, robotics, and industrial automation.

Host:

Awesome! Thanks for walking us through the comparison so thoroughly.

Speaker:

My pleasure. Sensor selection becomes much easier when teams connect the specs to the camera architecture.

Host:

Folks, that brings us to the end of yet another episode of e-con Systems' Vision Vitals. I hope that the insights we shared go a long way to simplify your understanding of these three Sony STARVIS sensors.

To explore e-con Systems' camera solutions based on these sensors, please visit e-con Systems dot com and use the Camera Selector to identify the right camera for your application.

If you already know what type of vision power your application needs and want to start the next level of discussion, reach out to camerasolutions@e-consystems.com.

Thanks for listening once again. We'll be back soon with another episode.

Have a great day!