Help Needed: Designing a Custom ToF Camera with VD55H1 Sensor Die

[magnus411]

Hello everyone,

I’m a computer engineering student looking to build a custom Time-of-Flight (ToF) camera around the VD55H1 sensor die. I have multiple projects I would love to do that require a TOF sensor/camera, but as I have searched around they are often quite expensive. As a student on a tight budget, I decided to build my own TOF camera instead —not only to cut costs but also to gain a lot of experience and do a fun project.

However, I’m finding the available documentation and reference designs a bit sparse, and I have several questions on how to get started. I have a lot of experience in low-level programming, but I'm relatively new to hardware design and PCB development.

I’ve settled on the VD55H1 (0.54 Mpix iToF sensor die), as I found most other TOF sensor dies has really small resolution, and most of my project requires a detailed point cloud.

Now for all of my questions:

The VD55H1 data brief references an illumination system (VCSEL + Laser driver). Is the “Laser driver” referred to in the documentation specifically for driving the VCSEL, or are these separate components (e.g., a VCSEL plus a separate driver IC)?

Where do I physically place the VCSEL relative to the sensor die on the PCB? (For example, do they need to be closely coupled or separated by some specific distance? Is there a guide for this? Is there some mathematical calculation for this?

The data brief mentions an application schematic and reference design (HW & SW) will be made available by ST, but I haven’t found a complete guide for the VD55H1 yet.

Are there recommended evaluation boards, design guides, or application notes, I can reference?

The sensor outputs RAW data over MIPI CSI-2. I know many STM32 MCUs do not directly support MIPI CSI-2. I’ve seen references to the STMIPID02, but I’m unsure if that’s the correct path. What other SoCs or MCUs should I be looking at instead of the STM32?

Are there recommended lens modules or optical assemblies specifically designed to use with the VD55H1?

Beyond the sensor, VCSEL, laser driver, and a suitable SoC/MCU, what else might I need? 

 Im sorry if these questions seams really ignorant or annoying, but Im just not sure where to start. I have tried my best to find information, but the info on the VD55H1 or similar designs are really sparse. 

Best regards

Magnus

[John E KVAM · Accepted solution]

I think it's a great idea, but you are going to have a lot of issues. Actually, way too many unless you plan on a PhD.

An Imager is a bare die. It means there is no plastic with a BGA or anything else. it's a high-tech, fantastic bit of kit, but it's only the silicon wafer. You can't just solder it to a board.

But to the right customer, one with millions of dollars' worth of machinery, that's fine. They can put it on a substrate, build a plastic housing around it, marry it to a VCSEL driver and VCSEL, and poof, they have a module. 

ST doesn't like to build modules. Sometimes we have to; but would rather not. 

There a quite a few module makers in the world and a customer could buy our die and hire one to make just what you want. 

Unfortunately to make that pay, there has to be a market for a large number of the things. And that guy might not want to bother making something you could use. Generally, they just make their finished product.

We did make some evaluation kits. But due to the small quantity they are massively expensive. And our module maker loves making new modules but hates mass production. So, we only get a small number.

And that leaves support. ST would love to support you. But it just doesn't pay unless the quantities are large. We have a team of experts, but they want to talk to your team of experts. We are just not set up to help a small company or a college student with a bare die project.

But if you have a killer idea and some real money to spend, please contact ST through the support page. Someone will call you, I'm sure.