Posts Tagged ‘ Light Emitting Diodes’



Home Security Monitor Camera

Written By:
Friday, December 17th, 2010

A home security monitor camera can alert you to the arrival of any guests long before they reach your door. A home security monitor camera can also be used as a baby monitor to keep a watchful eye over your child while they are awake or asleep. Finally, a home security monitor camera used in conjunction with an electronic door can be used as an entry/exit monitor, allowing the user to see who is at the door and allowing them access without the need to greet them at the door.

These are just some of the specific uses for a home security monitor camera. Of course, the use of a home security monitor camera for protecting your property both inside and out is also common. Most home digital video security systems have security monitor cameras and monitors as well as a Digital Video Recorder (DVR) unit to record what the cameras capture for later viewing or other use.

Let’s take a closer look at some the uses for a home security monitor camera. Our first example states that a home security monitor camera can alert you to the arrival of any guests long before they reach your door. This is particularly useful for homes in very rural settings or homes with fairly long driveways from the road to the house.

In this instance a digital video camera, preferably an outdoor night vision infrared camera can be mounted outdoors on a pole, tree, or similar structure with its field of vision focused at the driveway. When people or vehicles approach the house, you will be able to see them far in advance of reaching your door.

A particularly useful feature for this application is a camera with a motion detector. The motion detector is a Passive InfraRed (PIR) sensor that detects changes in infrared energy. A sudden change indicates movement to the sensor which is connected to a relay. When the detector senses motion, it activates the relay which in turn initiates the camera to begin recording.

Another use for a home security monitor camera is a baby monitor. In this case DVRs are seldom used as real-time (live) monitoring of the baby is the focal point of using the monitor camera. In fact, these systems have become so popular that specialty baby monitor cameras are now sold apart from digital video security systems.

These units are usually wireless cameras and monitor/receivers. The camera is an indoor night vision infrared digital video camera. The camera works by using near infrared spectrum radiation to illuminate the field of vision. The infrared illumination is normally provided by an array of infrared Light Emitting Diodes (LEDs) that surround the camera lens. These LEDs provide illumination for the camera in the near infrared spectrum.

The camera has a sensor that can see this illumination, but the human eye cannot. Therefore, baby monitor cameras can provide high quality monochrome or black and white video in darkness and normal color video in visible light. When operating in the night time mode the camera will not disturb the baby’s sleep because the LED light can be seen by the human eye.

Another specialized use of a home security monitor camera is for entrance/exit control. A digital video camera is usually mounted in such a position that its field of view will include any individuals that come to your door. The cameras can include audio monitoring as well and when combined with a remote electronic switching mechanism can make a very effective sentry control device. In addition to using these cameras at door entrances they work extremely well when combined with remote gate openers at driveway entrances also.

These are just a few of the more common specialized uses for home security monitor cameras. There are many more applications for using a home security monitor camera. Another particularly nice feature of these cameras is that they are easy enough to install yourself. In fact, in most cases installing your own digital video security camera system shouldn’t take much more time than a weekend.

Security Camera King has a variety of home security monitor camera systems. If you are interested in purchasing a home security monitor camera or would like more information, contact one of our security experts today via live chat or telephone. Click on the “Live Chat” button at the top of the page or call 1-800-866-573-8878 from Monday through Friday 9AM-6PM EST.

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Spy Camera DVR

Written By:
Monday, November 22nd, 2010

A spy camera DVR or Digital Video Recorder usually differs from typical digital video security system DVRs because of the necessity for portability. Most spy camera models capture video at a lower size than standard which also requires lest DVR capacity.

Before we talk about a spy camera DVR, let’s discuss what a typical digital video security system is and how it works. Then we’ll discuss how this differs from a spy camera system and finally, what different types of spy camera DVRs are available.

A typical, full sized digital video security system consists of three major components: 1. Digital video camera(s); 2. A DVR with a Digital Signal Processor or DSP; and, 3. One or more monitors. Each digital video camera captures video images by changing light energy into electrical energy that can be used to create digital video files. The DSP uses the data created by the digital video camera and actually creates the digital video file. The DSP stores the file on the DVR for later viewing on a monitor or the file can be viewed live on a monitor.

There are several optional features, deviations, and additions that can be made to the previous description, but that is a basic digital video system in a nutshell. There are two specifics we should mention about the digital video camera that may come into play with the use of a spy camera; how the images are captured and infrared imaging.

Digital video cameras work by focusing light from images onto a fairly small electronic sensor chip. There are two different sensor chips that can be used and although they differ slightly in how they transfer light energy into electrical energy they both produce the same product, data that can be used to create a video image. The sensors that are used are either a Charged Coupled Device or CCD and a Complimentary Metal Oxide Semiconductor or CMOS.

Both the CCD and the CMOS are also inherently sensitive to infrared radiation, specifically wavelengths or radiation called near infrared. This means with the proper lighting and filters a digital video camera can be designed to capture not only normal visible light images, but also infrared light images invisible to the human eye.

There are basically two methods of collecting security and surveillance video. The most popular method is overt recording. When capturing video overtly, there is no attempt to hide the video equipment. Covert recording is an attempt to capture video without the subject’s awareness. Covert recording systems are often called spy cameras or spy camera DVRs.

Most spy cameras achieve their status as “spy cameras” by disguising themselves within or as other objects. For example, Security Camera King has a vast selection of disguised or hidden (spy) cameras that are imbedded in or appear as exit signs, wall clocks, telephones, and many other items.

Some of these devices may also contain infrared Light Emitting Diodes or LEDs to illuminate areas in total darkness. As mentioned earlier, these infrared LEDs project a light that is invisible to the human eye but can be detected by an infrared digital video camera. As a result, these cameras can record video in total darkness.

Most of the spy cameras mentioned thus far can be connected to a basic standalone digital video security system that includes a standard DVR. The DVRs used in these systems are the like the hard disk drive in a computer. They contain a spinning plate and a magnetic head that moves about the plate recording the digital video files.

However, when we think of spy camera DVRs it is not the hard disk drive mentioned above. These spy cameras are often very small and compact or are imbedded in very small and compact objects. For example, Security Camera Kings product # HC-PEN Ink pen or HC-WATCH Wristwatch both record color video and audio. Their memory or spy camera DVR is built in solid state memory. Normally a special USB cable is used to transfer the data from this DVR to a personal computer.

Other types of spy camera DVRs may utilize a variety of small, non-mechanical solid state memory devices as their DVR medium of choice. For example, some spy camera DVRs consist of thumb drives, Flash memory cards like SD cards, Mini Compact Flash cards and the like.

Modern technological improvements have created physically smaller yet larger in capacity spy camera DVRs. Check out our full line of spy cameras in our on-line catalogue.


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Camera Mounted Infrared Illuminator

Written By:
Monday, August 2nd, 2010

A camera mounted infrared illuminator is used with most night vision infrared digital video surveillance and security cameras to provide invisible light that is used to create an infrared digital video. The illuminator is normally aimed in the exact same direction of the camera lens so that it can provide infrared light beams to illuminate the target area. Infrared illumination can be “seen” by the camera, but cannot be seen by the human eye.

Let’s take a closer look at how a night vision infrared digital video security camera works in order to appreciate the need for the camera mounted infrared illuminator.

A night vision infrared digital video security camera can produce high quality color video footage when there is enough visible light present. When there is not enough visible light present or when in total darkness, a sensor on the camera switches it into the infrared mode. Digital video recorded under the infrared mode is high quality video footage as well, but is monochromatic or black and white, since infrared light does not emit color.

These cameras create a video image by using one of two sensors that convert light energy into electrical energy that can be quantified and used to create a digital video picture. The sensors that are normally used are the Charged Coupled Device or CCD, or the Complimentary Metal Oxide Semiconductor or CMOS. The camera lens focuses the light from the image onto the sensor which then converts the light image into an electronic image which can be viewed on a monitor or stored as a digital video file.

Both the CCD and CMOS can be constructed with various sensitivities to light. Some cameras can produce full-color, high quality digital video with as little as .002 lux or less of light. These cameras are usually called day/night vision cameras and still require visible light to operate properly; they are infrared sensitive cameras.

A camera mounted infrared illuminator is required on night vision infrared digital video cameras to provide plenty of “light” to illuminate the subject. However, in this case the light is actually infrared radiation from the near infrared spectrum. This light or radiation has a similar effect as a flood light or spot light would on a normal visible-light digital video camera.

Most camera mounted infrared illuminators are created from several infrared Light Emitting Diodes or LEDs. The LEDs are able to create a sufficient amount of radiation that can be focused in the direction of the camera’s field of view. The advantage of using LEDs is that they use a relatively low amount of electrical energy and are small and compact.

The LEDS are normally arranged in an array that surrounds the outside of the camera’s lens or is in a grouping off to the side of the lens but aimed in the same direction as the camera. Generally the more LEDS used the greater the angle and the longer the distance of the effective infrared field of view. For this reason, every night vision infrared digital video camera has an effective target range.

If you are considering the purchase of an infrared night vision camera, be certain that the camera matches the range that you need for the job. There are a variety of different cameras available based on their effective range. Range values for cameras usually begin around 20 to 30 feet with cameras that have ranges of up to 200 feet or more. Cameras are more expensive for higher ranges, because of the extra LEDs that are used for the camera mounted infrared illuminator.

Some cameras ranges and angle of field of view can be extended by using additional infrared LED illuminators. However, these are not camera mounted infrared illuminators; they are mounted separately on their own and must be manually adjusted to ensure that they are aimed properly at the field of view of the camera.

Camera mounted infrared illuminators are an integral and necessary component of any infrared digital video camera. They supply the infrared “light” or radiation that is needed to illuminate the target area for the camera. Normally, the source for this radiation is an array of infrared LEDs that surround the camera lens or are located on the camera. Additional LED illuminators can also be purchased as accessories.

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