{"id":997,"date":"2018-07-18T16:25:33","date_gmt":"2018-07-18T16:25:33","guid":{"rendered":"https:\/\/www.1stvision.com\/machine-vision-solutions\/?p=997"},"modified":"2023-04-05T12:17:54","modified_gmt":"2023-04-05T16:17:54","slug":"5-benefits-of-using-strobed-lighting-for-machine-vision","status":"publish","type":"post","link":"https:\/\/www.1stvision.com\/machine-vision-solutions\/2018\/07\/5-benefits-of-using-strobed-lighting-for-machine-vision.html","title":{"rendered":"5 benefits of using strobed lighting for machine vision applications"},"content":{"rendered":"

\"Gardasoft<\/a>Pulsing (aka strobing)\u00a0 a machine vision LED\u00a0 light<\/a> <\/span><\/em>is a powerful technique that can be beneficial to machine vision systems in various ways.<\/p>\n

This blog post outlines 5 benefits you will receive from pulsing\u00a0 a LED\u00a0 light head.\u00a0 Gardasoft<\/a><\/strong><\/span> is an industry leader in strobe controllers capable of driving 3rd party LED light heads or custom LED<\/em><\/span><\/a> banks for machine vision.<\/em><\/span><\/a><\/p>\n

1 – Increase the LED light output<\/strong><\/h1>\n

It is common to use pulsed light to “freeze” motion for high speed inspection.\u00a0 But, when the light is on only a short term in burst, its possible to increase the light output beyond the LED manufacturers specified maximum, using a technique called “Overdrive”.\u00a0\u00a0 In many cases, the LED can be powered by 10X over the constant current power input in turn providing brighter pulses of light.\u00a0 When synchronized with the camera acquisition, a brighter scene is generated.\"Gardasoft<\/a><\/p>\n

2 – Extend the life of the LED\u00a0<\/strong><\/h1>\n

As mentioned in the first benefit, strobing a LED light head only turns on the LED for short period of time.\u00a0 In many cases, the duty cycles are very low which extends the life of the LED and any degradation in turn, keeping the scene at a consistent brightness for years.\u00a0 (i.e. If the duty cycle is only 10%, the lifetime of the LED head will increase by 10%)<\/p>\n

3 – Ambient Light control<\/strong><\/h1>\n

Ambient light conditions frequently interfere with machine vision measurements and these issues can be solved by pulsing and over driving the system\u2019s LEDs. For example, over driving the LED by 200% doubles the light intensity and enables the camera exposure to be halved, so reducing the effects of ambient light by a factor of 4.\u00a0 The end result is the cameras exposure is only utilizing light from the give LED source and NOT ambient light.<\/p>\n

4 – High speed imaging and Increased depth of field<\/strong><\/h1>\n

Motion blur in images from fast-moving objects can be eliminated with appropriate pulsing of the light.\u00a0 In some cases a defined camera exposure will be good enough to freeze motion (read our blog on calculating camera exposure<\/a>),<\/strong><\/span> but may suffer in light intensity with constant illumination.\u00a0 “Over driving” a light can boost the output up to 10x its brightness rating in short pulses.\u00a0 Increased brightness could allow the whole system to be run faster because of the reduced exposure times.\u00a0 Higher light output may also allow the aperture to be reduced to give better depth of field.<\/p>\n

\"\"<\/a>
Extended Depth of Field (DOF) is achieved with a brighter light allowing the f-stop to be turned down<\/figcaption><\/figure>\n

Gardasoft controllers include our patented SafePower\u2122<\/span> and SafeSense\u2122<\/span> technology which prevents over driving from damaging the light.<\/p>\n

5 -Multi-Lighting schemed & Computational Imaging<\/strong><\/h1>\n

Lighting controllers can be used to reduce the number of camera stations. Several lights are set up at a single camera station and pulsed at different intensities and duration’s in a predefined sequence.<\/p>\n

\"CCS<\/a>
Generate edge and texture images using shape from shading<\/figcaption><\/figure>\n

Each different lighting can highlight particular features in the image. Multiple measurements can be made at a single camera station instead of needing multiple stations and reduces, mechanical complexity saving money. For example, sequentially triggering 3 different types of lighting could allow a single camera to acquire specific images for bar code reading, surface defect inspection and a dimensional check in rapid succession.<\/p>\n

Pulsing can also be used for computational imaging, where a component is illuminated sequentially by 4 different lights from different directions. The resultant images would be combined to exclude the effect of random reflections from the component surface.\u00a0 Contact us and ask for the white paper on Computational imaging to learn more<\/em> <\/span><\/a><\/p>\n

\"CCS<\/a>
The images on the right (top and bottom) were taken with bright field and dark field lighting. The left images is the the result of the computational imaging combining the lighting techniques allowing particles and water bubble to be seen<\/figcaption><\/figure>\n

Pulsed multiple lighting schemes can also benefit line scan imaging by using different illumination sources to capture alternate lines. Individual images for each illumination source are then easily extracted using image processing software.<\/p>\n

In conclusion, strobe controllers can provide many benefits and save money in an overall setup more than the cost of a controller!<\/p>\n

1st Vision has additional white papers on the following.\u00a0 Contact us an ask for any one of these informative white papers – Simply send an email and ask for 1 or all of the white papers.<\/strong><\/span><\/a>
\n1- Practical use of LED controllers<\/em>
\n2 – Intelligent Lighting for Machine Vision Systems<\/em>
\n3- LED Strobe lighting for ITS systems<\/em>
\n4 – Liquid Lens technology and controllers for machine vision.
\n5 – Learn about computational imaging and how CCS Lighting<\/strong> <\/span><\/a>can help
\n<\/em><\/p>\n

\"Contact<\/a><\/p>\n

1st Vision\u2019s<\/span><\/strong><\/a> sales engineers have over 100 years of combined experience to assist in your camera selection.\u00a0 With a large portfolio of lenses<\/a>, cables<\/a>, NIC card<\/a> and industrial computers<\/a>, we can provide a full vision solution!<\/p>\n

Related Topics<\/strong><\/p>\n

Learn how liquid lenses keep continuous focus on machine vision cameras when the working distance changes.<\/a><\/p><\/blockquote>\n