Designing a Passive Lidar Detector Device

Posted21 days agoActive16 days ago

speckx

62 points

5 comments

atredis.comTech Discussionstory

informativeneutral

Debate

20/100

Lidar TechnologyCPU DesignDetection Systems

Key topics

Lidar Technology

CPU Design

Detection Systems

Discussion Activity

Moderate engagement

First comment

10m

Peak period

84-96h

Avg / period

2.5

Key moments

01Story posted
Dec 15, 2025 at 5:01 PM EST
21 days ago
Step 01
02First comment
Dec 15, 2025 at 5:11 PM EST
10m after posting
Step 02
03Peak activity
7 comments in 84-96h
Hottest window of the conversation
Step 03
04Latest activity
Dec 20, 2025 at 3:03 PM EST
16 days ago
Step 04

Generating AI Summary...

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Discussion (5 comments)

Showing 10 comments

MezzoDelCammin

17 days ago

2 replies

I admit it's a nice experiment, but I guess the title should be "detecting iPhone Lidar".

Both the 60Hz frequency and 940nm wavelength are fairly specific. There's a whole world of different wavelengths (1550nm is fairly common) and frequencies (up to 1MHz isn't particularly exceptional).

There's been a whole thread on the topic here:

https://news.ycombinator.com/item?id=46110395

MPSimmons

17 days ago

Agreed, I immediately thought of vehicles, but this is cool too.

aidenn0

16 days ago

Right, I wonder if they considered a pulse-detector with a dichroic filter and a 555?

vzaliva

17 days ago

2 replies

If you are sensitive to flashing - do not try to open this link. It is impossible to read because of videos of flashing lights.

elric

17 days ago

2 replies

Makes me wonder about how safe lidar is for humam and animal eyeballs?

estimator7292

16 days ago

I have some very bad news for you about the kinds of light emitted by the sun and also your oven

garbagewoman

17 days ago

The videos are of invisible wavelengths of light transformed into visible light. Why does that make you ponder the safety of the infrared light?

BrianGragg

17 days ago

Reader view ftw!

jonas21

17 days ago

I thought the front and back sensors on the iPhone used different technology -- with the front using structured light (displacement in a dot pattern), and the back using time of flight. Did this change at some point?

mubou2

21 days ago

Delete my account, YC, you fucking assholes.

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ID: 46281355Type: storyLast synced: 12/19/2025, 7:15:35 PM

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