Posts Tagged ‘ digital video image’

IR Bullet Camera

Written By:
Monday, May 2nd, 2011

When looking for versatility in a digital video security camera nothing may offer you more than an IR bullet camera (InfraRed bullet camera).  Among the most popular types of cameras these days, the IR bullet camera usually comes packed with dozens of extra features, thanks to modern technology.  In the following article, we’ll take a look at digital video security cameras and how they work and especially how an IR bullet camera works.

There are three major types of digital video security cameras based on shape; the box type, the dome type, and the bullet type.  For many years the favorite has always been the box type.  Although box type cameras are somewhat obtrusive, they are versatile because you must purchase the lens separately, which allows you to change the field of view characteristics when ever you want.  Also, box type cameras are intended for indoor use, but can easily be converted to outdoor use by placing the camera in an outdoor rated housing.

Next in line is the dome camera.  Dome cameras are used indoors or outdoors but it seems as though the majority of their applications lean toward indoor installation and mounting.  These camera are fast becoming competitive with box cameras because they are small and unobtrusive, versatile with many features, and are easy to mount to the wall or ceiling.  Dome cameras can be purchased as indoor, outdoor, or indoor/outdoor models.  The can also be sold as vandal proof because once they are properly mounted on the ceiling it would be very difficult for a vandal to change the position of the camera.

Finally, there is the IR bullet camera or just a plain bullet camera.  They are so called because their shape resembles the shape of a bullet.  Bullet cameras may be mounted in several different ways.  Regardless if they are mounted on the wall or ceiling, bullet camera mounts normally have a bit of an extension arm that aids in getting the camera in the exact position you desire.  The down side to this is that the camera can become vulnerable to vandalism because it can be easily repositioned.

Now that we’re familiar with the types of cameras, let’s talk a little bit about how they work.  As a matter of fact, all three types of cameras produce digital video images in the same manner and this is how they do it.

The lens’ job is to gather the reflected light from images in it’s field of view, and focus them onto a very small censor chip (the chip ranges from 1/4 to 1/2 square inch).  The sensor chip is a high specialized electronic chip that can convert light energy into electrical energy.  The electrical energy can be measured and the values used to recreate the actual image as a digital video image on an electronic display monitor.

There are two different sensor chips that may be used and although they may go about producing the video image differently, the both produce the same result; digital video images.  The names of these sensor chips are the Charged Coupled Device or CCD and the Complementary Metal Oxide Semiconductor or CMOS.

These sensor chips are incredibly interesting because they possess an unusual trait.  They both are sensitive to near infrared radiation.  This is the type of radiation that is given off by TV remotes, DVD players, etc.  It is harmless to humans but even better for the security camera industry, it is completely invisible.  Therefore, it could be pitch dark and the camera can still produce a video image as if a spot light were shining in its direction.

It does this by the use of InfraRed producing Light Emitting Diodes or IR LEDs.  Generally, the more LEDs used to produce infrared “light” the longer the range of the camera in total darkness.  This is where the bullet camera comes in.

Due to its shape an IR bullet camera can really pack a large array of IR LEDs around its lens.  Some camera boast as many as 78 or more and a range if 300 feet.

To summarize, the IR bullet camera is a versatile digital video security tool.  It provides the same quality video as box camera but doesn’t require an additional housing.  It provides the capability for IR imagery like a dome camera but it has a much longer range potential due to the size and shape of the camera.


Wireless Wall Clock Camera

Written By:
Tuesday, February 15th, 2011

Sometimes it’s necessary to keep a watchful eye covertly, and a wireless wall clock camera is just the device for the job. Security Camera King offers several different types of hidden cameras, including wireless wall clock cameras. These cameras are built in such a way that detection of surveillance is almost impossible.

Our security experts are often asked how these cameras actually work and how they can be concealed in an object like a clock. In the following article we’ll talk about how a wireless wall clock camera works an mention the types available for purchase through Security Camera King.

The key factor behind hidden or disguised digital video security cameras is advanced technology. In the no to distant past, security and surveillance cameras were analog based. Since they are now digital, that has allowed the security camera industry to share the benefits of technological advances found in the personal computer and electronic industries. This in turn has yielded incredibly small, high quality cameras that can capture video images in a variety of different conditions.

Creating a digital video image using a wireless wall clock camera begins with the camera’s lens. Objects have a natural tendency to reflect light. The light that is reflected is gathered by the lens and focused on an electronic sensor. Many hidden cameras use a highly accurate 3.7 mm wide angle lens. To get an appreciation for the size of this lens, hold two nickels together. The thickness of two stacked nickels is a little greater than the entire size of a 3.7 mm lens. The wide angle feature allows this small lens to have a proportionately larger field of view.

The lens focuses the light image on a small electronic sensor. One of two different sensors is used. A Charged Coupled Device or CCD or a Complementary Metal Oxide Semiconductor or CMOS converts the light energy into electrical impulses. The CCD and CMOS go about the process a little differently, but both yield the same end result; electrical impulses that can be measured and used to create a digital video image.

As a side note, CCDs have historically produced a higher quality image with a greater demand for electrical power while CMOSs have produced a slightly lesser quality image with a lesser demand for power. However, as technology advances, both CCDs and CMOSs are approaching an equal state of quality and power demand.

All of Security Camera King’s wireless wall clock cameras use CCDs. One would think that the electronic sensor would need to be rather large, especially when using a wide angle lens. However, our wireless wall clock cameras use a very small 1/4 or 1/3 inch CCD. Using a 3.7 mm lens and such a small CCD, it should become obvious how easy it is to disguise the camera with the clock face.

After the light images are created into measurable electrical impulses by the CCD, the camera then converts this analog data to binary or digital form by using an analog-to-digital converter. The analog-to-digital converter resides in a very small Integrated Circuit or IC chip that takes up very little space.

Now the video data is ready for transmitting. Once again a relatively small IC chip comprises the transmitter. The circuit converts the digital data into radio waves that can be sent by the transmitter to a corresponding wireless receiver.

Our wireless wall clock cameras use 2.4 GHz radio technology; the same technology used by many land-line based wireless phones. This technology offers a strong, clear signal with very little interference.

Normally the receiver is located near the Digital Video Recorder or DVR unit and is connected to it by a cable. Once the wireless wall clock camera video signal reaches the receiver, it is transferred to the DVR where it can be displayed on a monitor and viewed live and/or stored on the DVR’s hard disk drive for archiving or later use.

Security Camera King offers four different wireless wall clock cameras. We offer a “standard” looking wall clock that looks like any plain circular wall clock found in an office or home. We also offer a more sophisticated looking clock camera with humidity and temperature indicators. Each of the two designs offers either a black and white video image or a color video image. The black and white video images models will produce a high quality image in very low light conditions (0.003 lux for example). Check our “Wireless Hidden Cameras” web page.