What Are the Benefits of CMOS vs CCD Machine Vision Cameras?

Industrial machine vision cameras historically have used CCD image sensors, but there is a transition in the industrial imaging marketplace to move to CMOS imagers. Why is this?.. Sony who is the primary supplier of image sensors announced in 2015 it will stop making CCD image sensors and is already past its last time buy. The market was nervous at first until we experienced the new CMOS image sensor designs. The latest Sony Pregius Image sensors provide increased performance with lower cost making it compelling to make changes to systems using older CCD image sensors.

What is the difference between CCD and CMOS image sensors in machine vision cameras?

Both produce an image by taking light energy (photons) and convert them into an electrical charge, but the process is done very differently.

In CCD image sensors, each pixel collects light, but then is moved across the circuit via current through vertical and horizontal shift registers. The light level is then sampled in the read out circuitry. Essentially its a bucket brigade to move the pixel information around which takes time and power.

In CMOS sensors, each pixel has the read out circuitry located at the photosensitive site. The analog to digital circuit samples the information very quickly and eliminates artifacts such as smear and blooming. The pixel architecture has also radically changed moving the photosensitive electronics to be more efficient in collecting light.

6 advantages of CMOS image sensors vs CCD

There are many advantages of CMOS versus CCDs machine vision cameras outlined below:
1 – Higher Sensitivity due to the latest pixel architecture which is beneficial in lower light applications.
2 – Lower dark noise will contribute to a higher fidelity image.
3 – Pixel well depth (saturation capacity) is improved providing higher dynamic range.
4 – Lower Power consumption. This becomes important as lower heat dissipation equals a cooler camera and less noise.
5 – Lower cost! – 5 Megapixel cameras used to cost ~ $2500 and only achieve 15 fps and now cost ~ $450 with increased frame rates.
6 – Smaller pixels reduce the sensor format decreasing the lens cost.

What CMOS image sensors cross over from existing CCD image sensors?

1stVision can help in the transition starting with crossing over CCDs to CMOS using the following cross reference chart. Once identified, use the camera selector and select the sensor from the pull down menu.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera selection. With a large portfolio of lenses, cables, NIC card and industrial computers, we can provide a full vision solution!

Ph: 978-474-0044 / info@1stvision.com / www.1stvision.com

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What is the fastest 2.4MP GigE camera at the lowest price point? Dalsa’s new Nano M1950 / C1950!

Teledyne Dalsa has released the latest addition to the Genie Nano family. Introducing the Nano M1950 and C1950 cameras using the Sony Pregius IMX392 image sensor. This is a great replacement for older Sony ICX818 CCD sensors.

These latest Nano models offer 2.4 MP (1936 x 1216) resolution with a GigE interface in color and monochrome with up to 102 frames per second utilizing TurboDrive.

What’s so interesting about the Nano M1950 and C1950 models?

2.4 MP resolution with the speed of the popular IMX174, but at the price of the IMX249:
Sony Pregius image sensors in a given resolution has created paired sensors, one being faster at a higher price and one slower at a lower price. The Nano M1940 / C1940 cameras use the IMX174 which is a great sensor and historically had the fastest speed at 2.4MP in GigE, but at a premium. We could opt for the Nano M1920 / C1920 cameras with the IMX249 at a lower price, but sacrificed speed.

Until now! – The latest Nano M1950 / C1950 models with the IMX392 provides the higher speed of the M1940 / C1940 cameras, but at the lower price of the Nano M1920 / C1920 cameras.

2.4MP resolution using a 1 /2 in sensor format, provides cost savings on lenses.
Thanks to the Sony Pregius Gen 2 pixel architecture, the pixel size is 3.45um, allowing the same resolution and eliminating the added cost of larger format lenses found in the IMX174 / IMX249 sensors which were 1 / 1.2″ formats.

Contact 1stVision to get our recommendations on lens series designed for the 3.45um pixel pitch.

When would you use the Sony Pregius IMX392 versus the IMX174 and IMX249 sensors?

The Sony Pregius IMX174 / IMX249 images still have an incredible dynamic range due to the pixel architecture found in the first generation image sensors. (Read more here on Gen 1 vs Gen 2). If you need dynamic range, with large well depths of 30Ke-, then use the IMX174 / IM249 sensors.

I’m so confused! Where can I get the specs on the new Nano M1950 / C1950, understand what sensors are in what cameras and get a quote?

The tough part today, is that there a ton of model #’s in the Sony Pregius sensors lineup and in turn camera product lines. Here’s a brief table to help with links to spec’s, related image sensors and a link to get a quote.

Sensor          Model
IMX174         Nano M1940 / C1940          GET QUOTE
IMX249        Nano M1920 / C1920           GET QUOTE
IMX392        Nano M1950 / C1950           GET QUOTE

Contact us to help in the specification and providing pricing

Ph: 978-474-0044 / info@1stvision.com / www.1stvision.com

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Sony Pregius sensor “Generations” – What do those differences mean for machine vision?

Machine Vision cameras continue to reap the benefits of the latest CMOS image sensor technology since Sony announced the discontinuation of CCD’s. We have been testing and comparing various sensors over the years and have always come back to using Sony Pregius sensors when dynamic range and sensitivity is needed.

If you’ve been watching the technology shift from CCD’s to CMOS, you have probably also seen a ton of new image sensor names within the “Generations”. Honestly, its hard to keep track of all of Sony’s part numbers, so we will try to give you some insight into the progression of Sony’s Pregius image sensors used in industrial machine vision cameras.

1 – First, how can I tell if its a Sony Pregius generation sensor?

Sony has prefixes of the image sensors which make it easy to identify if its an ExView HAD sensor or Pregius sensor. Previous CCD, EXViewHAD sensors primarily in the last 10 years had a prefix of “ICX”. Example: ICX285, which was a great sensor back in the day. All new generation Sony Pregius sensors have a prefix of “IMX.” Example: IMX174 – which today is one of the best sensors for dynamic range..

1stVision’s camera selector can be filter by “Resolution” and you can scroll and see the sensors with a prefix of IMX. CLICK HERE NOW

2 – What is the differences in the “Generations” of Sony Pregius Image sensors?

Sony Pregius Generation 1: This primarily consisted of a 2.4MP resolution sensor with 5.86um pixels BUT had a well depth (saturation capacity) of 30Ke- and still unique in this regard within the generations. Sony also brought the new generations to the market with “slow” and “fast” versions of the sensors at two different price points. In this case, the IMX174 and IMX249 were incorporated into industrial machine vision cameras providing two levels of performance. Example being Dalsa Nano M1940 (52 fps) using IMX174 vs Dalsa Nano M1920 (39 fps) using IMX249, but the IMX249 is 40% less in price.

Sony Pregius Generation 2: The primary goal of Sony was to expand the portfolio of Pregius sensors which consists of VGA to 12 MP image sensors. However, the pixel size decreased to 3.45um along with well depth to ~ 10Ke-, but noise also decreased! The smaller pixels allowed smaller format lenses to be used saving overall system cost. However this became more taxing on lens resolution being able to resolve the 3.45um pixels! In general it offered a great family of image sensors and in turn an abundance of machine vision industrial cameras at lower cost than CCD’s with better performance.

1stVision’s camera selector can be filter by “Resolution” AND pixel size that correspond to one of the generations. You will have a list of cameras in which you can select those starting with IMX!. I.e All Generation 2 sensors will be 3.45um, and can narrow to a desired resolution. CLICK HERE NOW

Sony Pregius Generation 3: Sony’s has taken the best of both the Gen 1 and Gen 2 to create Gen 3! The pixel size increased to 4.5um increasing the well depth to 20Ke-! This generation has the fastest data rates, dynamic range and lowest noise. The family will expand from VGA to 7.1MP as well. We are just starting to see Gen 3 sensors in our machine vision camera lineup and expecting more to come through 2019+.

Sony Pregius image sensor Comparison Chart

Sony’s Pregius Product line up for machine vision industrial cameras below for reference as of April 2019

Sony Pregius product line up — Courtesy of Sony

Contact us to help in the specification of your imaging components

Ph: 978-474-0044 / info@1stvision.com / www.1stvision.com

How can we help answer your questions about industrial imaging? We have used several terms you may not be familiar with and would like to help in your education. Below are some related blogs that will help. Or contact us via email or phone number as we love to help educate our customers!

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Learn about the new 5GigE camera interface

Machine vision interfaces have continued to evolve over the years increasing data throughput and cable lengths. Commonly used interfaces are GigE and USB3. However, 5GigE is an interface now gaining attention in the industrial imaging / machine vision market with some nice advantages.

We will outline the benefits of 5GigE, but first, lets give a brief overview of the commonly used camera interfaces, with their pluses and minuses:

GigE / GigE Vision

110 MB/s of sustainable throughput. In real world terms, a HD, 2MP camera can get 50-55 fps in 8 bit mono or 8 bit color mode. Note, this isn’t real HD, since you need 60 FPS.
Data cable lengths up to 100m using regular CAT 5e/6 cable.
Easy to put multiple cameras on a system.

USB 3 / USB3 Vision

420 MB/s of data throughput. A HD 2MP camera can run 60 fps in 8 bit mono or color and can also run RGB at 60 FPS no problem. With the higher throughput, a 5MP camera can achieve 85 fps in 8 bit mode.
Data cables up to 5 meters and up to 20 meters with active cables. However, active cables can be quite costly, adding up to $200 in cost.
Not as easy as GigE to put multiple cameras on a system, and gets harder with each additional camera, especially if you have limited USB3 controllers.

As a note, there is no cost difference when using cameras with the same sensor from the same manufacturer with USB or GigE! They will cost about the same with no premium for one interface over the other.

What are the limitations of GigE and USB3 now solved by 5GigE?

USB3 is limited in cable length, so going faster than GigE is great, but you can not have long cable lengths.
GigE has cable lengths up to 100 meters, but is limited to ~ 110MB/s of data, so you do not have the high frame rates as in a USB3 camera.
USB3 in 4+ camera systems is not as stable as GigE AND you’re still limited on cable lengths.

Wait! – What about 10GigE?

Up until now, 10G was the next interface. However, the jump to 10G has quite a few limitations as outlined below.

Heat generation is significant, so cameras are large and not in the smaller 29 x 29mm cube form factor.
Not a lot of demand for very high speed 10G, so not a lot of sensors being offered
Minimal number of manufacturers for 10G, higher cost.
Special cabling, either optical or high quality cat 7.

What we have found is that there are several types of applications for 10G cameras and are as follows

Applications where you need 10G of speed of course (high resolution + fast frame rates)
Require greater than 110MB/s of data and need long cable lengths.
Where there is the required combination of 110MB/s for high frame rates, multiple cameras and long cable lengths, 10G is a perfect solution.

We have seen that the need for higher bandwidth + long cable lengths is more prominent vs. the real need for 10GigE!

Introducing 5GigE that provides increased bandwidth, long cable lengths at reasonable prices! or N Base T.

5GigE (also known as N Base T) has become a new standard for industrial, machine vision cameras.

In the general compute world, a much much larger market than vision, there has also been a need to go faster than GigE. However, the issue of replacing the existing cabling is the major issue preventing this. If you think of a big box store, say a Home Depot for instance, the amount of cabling is huge. Ripping that out and rewiring far exceeds the cost of the equipment to use it!

5G was made to go faster, but use existing cabling. Regular cat6e cable can be used, and 5G is a subset of 10G, so all switches etc. can be kept in service.

5G gives users in the vision market USB3 speeds, but with ALL of the regular GigE features, at a very small premium!