FAQs

No. IMPERX does not ship test reports with each camera. These test reports, called Passports, can be requested from IMPERX. Passports show the factory test results and other critical information about the configuration of the camera as it is configured and tested in the factory. Passports contain the following information;

IMPERX Inc. Bobcat Camera Passport Info & Parameters

Topic: Camera Manufacturing Test Reports

Keywords: Test Reports, Camera Configurations, Passports

No, a customer should not consider changing Image Sensors.   Cameras are configured in the factory using very specialized proprietary software applications along with special test fixtures.  This configuration, unique to each camera and sensor, is stored in memory on the camera.  A replacement sensor would require re-configuration in the factory. Also working on a camera requires a cleanroom environment and sound ESD measures.  Any attempt to repair or modify a camera in the field voids the warranty.

Topic: Remove and replace image sensor

Keywords: Sensor, Repair, Replace

Bobcat Cameras do not contain any user accessible non-volatile memory that can be used to store images, data, or any user files.

User control interfaces provide functionality only for control of the operating parameters of the camera.  Camera feature access is performed by reading or writing control sequences to internal registers within the camera.  The structure of the command and response sequence is outlined in the Bobcat Camera User’s Manual.

Internal volatile memory is used only to temporarily buffer image data prior to transition.  Image data is not stored or buffered in any non-volatile memory.  All volatile memory is lost upon loss of external power.  The camera does not contain batteries or alternate sources of power.

Topic: Non-volatile memory for cameras

Key-Words: Memory, Volatility, Architecture, Security

All IMPERX standard model cameras are built using Grade 1 Image Sensors. Custom Cameras may use other grade sensors depending on the desire of the customer.

Topic: Sensor Grade

Key Words: Image Sensors, Grade, Class

Image Sensors are graded based on the number of pixel (dark field defective bright and bright field defective dark), cluster, and column defects.  These numbers vary based on sensor part number (size). One must review the specifications for the sensor in question.

Topic: Sensor Grade

Key Words; Image Sensors, Grade, Class

In addition to the size of the sensor, the manufacturer of the sensor, and the number of taps, customers have a number of options of lens mount adapters, type of color, and optical filters.

Topic: Camera Options

Key-Words: Options, Color, Lens Mount, Filters

Yes. All Imperx Cameras Control Software released after 2014 supports Windows 10.

Topic: Software compatibility with Windows 10

Keywords: Control Software, Windows 10

If you cannot see the Imperx CameraLink camera in the list of available ports, then the associated .dll file that came with your frame grabber is not in the correct location.  The Bobcat CameraLink configurator GUI is looking in the C:\Windows\System32\ folder for the clsrxxx.dll (where “x” would indicate the specific manufacturer Camera Link Serial .dll that came with your frame grabber.)  If the file is not in the \System32 folder, please copy the file into this folder and re-open the CameraLink Configurator.

Applicable Products: Cameras (CameraLink)

Topic: CameraLink serial dll location

Keywords: CameraLink, FrameGrabber

A CCD imager is composed of a two-dimensional array of light sensitive pixels. In general, the majority of the pixels have similar sensitivity. Unfortunately, there are some pixels which sensitivity deviates from the average pixel sensitivity. A defective pixel is defined as a pixel whose response deviates by more than 15% from the average response. In extreme cases these pixels can be stuck ‘black’ or stuck ‘white’ and are non-responsive to light. There are two major types of pixel defects – “Defective” and “Hot”.

1. ”Defective” – these are pixels which sensitivity deviates more than 15% due to fluctuations in the CCD manufacturing process. Two type of defective pixels are possible:
   1. “DARK” is defined as a pixel, whose sensitivity is lower than the sensitivity of the adjacent pixels. In some cases, this pixel will have no response (completely dark).
   2. “BRIGHT” is defined as a pixel, whose sensitivity is higher than the sensitivity of the adjacent pixels. In some cases, this pixel will have full response (completely bright).
2. “Hot” – these are pixel, which in normal camera operation behaves as normal pixel (the sensitivity is equal to the one of the adjacent pixels), but during long time integration behaves as a high intensity bright pixel. In some cases, this pixel will have full response (completely bright).

2.16.1 Static Pixel Correction

Static Defective and Hot pixel correction works with predetermined and preloaded Defective and Hot pixel maps. During factory final testing, our manufacturing engineers run a program specially designed to identify these ‘defective’ and “hot” pixels. The program creates a map file which lists the coordinates (i.e. row and column) of every defective pixel. This file, called the Defect Pixel Map, is then downloaded into the camera’s non-volatile memory.

Users may wish, however, to create and to upload their own DPM file because of the uniqueness of their operating environment or camera use.

When ‘Defective Pixel Correction’ is enabled, the camera will compare each pixel’s coordinates with entries in the ‘defect’ map. If a match is found, then the camera will ‘correct’ the defective pixel. When ‘Hot Pixel Correction’ is enabled, the camera will compare each pixel’s coordinates with entries in the ‘defect’ map. If a match is found, then the camera will ‘correct’ the hot pixel. The "Defective/Hot Pixel Map" can be displayed upon user request.

2.16.1 Dynamic Pixel Correction

Dynamic pixel correction works without preloaded pixel maps. When this option is enabled, the camera determines which pixel needs correction and performs the correction automatically. Static and Dynamic “Defective Pixel Correction” and “Hot Pixel Correction” can be enabled independently or simultaneously.

In order to enable or disable defective pixel correction, open the Data Output menu from your Bobcat GUI. Select which type of pixel correction you’d like to enable by using the drop-down menus to the lower right of the menu, seen above.

Corrections:

DPC – enables Defective Pixel Correction (DPC). Each camera comes with a built-in Defective Pixel Map (DPM) to correct for defective pixels. The user can upload a custom DPM.

HPC – enables Hot Pixel Correction (HPC). Each camera comes with a built-in Hot Pixel Map (HPM) to correct for hot pixels. The user can upload a custom HPM

Topic: Defective/Hot Pixel Data Correction

Keywords: Hot pixel correction, defective pixel correction, hot pixel map, defective pixel map, HPC, DPC, HPM, DPM

<!–*OBTAINING INFORMATION FOR CHEETAH SPECIFIC “Fixed pattern noise” –>

The camera exposure can be controlled using an external pulse, supplied to the camera. The pulse duration determines the exposure. For stable operation, this pulse MUST be synchronized with the camera frame timing. Please refer to “I/O Control” section for pulse mapping information.

Applicable Products: Bobcat cameras

Topic: External Exposure Control

Keywords: External, Exposure Control

A CCD imager is composed of a two dimensional array of light sensitive pixels. Each pixel within the array, however, has its own unique light sensitivity characteristics. Most of the deviation is due to the difference in the angle of incidence and to charge transport artifacts. This artifact is called ‘Shading’ and in normal camera operation should be removed. The process by which a CCD camera is calibrated for shading is known as ‘Flat Field Correction ‘This feature is available as a standard feature only for cameras with 1.0” optical format or bigger.

The BOBCAT series of cameras incorporate a Flat Field Correction mechanism. The Flat Field Correction mechanism measures the response of each pixel in the CCD array to illumination and is used to correct for any variation in illumination over the field of the array. The optical system most likely introduces some variation in the illumination pattern over the field of the array. The flat field correction process compensates for uneven illumination, if that illumination is a stable characteristic of each object exposure.

During factory final testing, our manufacturing engineers run a program specially designed to identify the shading characteristics of the camera. The program creates a Flat Field Correction file, which contains coefficients describing these shading characteristics. This file is then downloaded into the camera’s non-volatile memory. When Flat Field Correction is enabled, the camera will use the Flat Field Correction coefficients to compensate for the shading effect.

Each IMPERX camera is shipped with the Flat Field Correction file that was created for that camera during factory final testing. Users may wish, however, to create their own Flat Field Correction file because of the uniqueness of their operating environment (i.e. lens, F-stop, lighting, etc.). Therefore, IMPERX provides a Flat Field Correction utility that allows users to generate a Flat Field Correction file. This file can then be downloaded into the camera. While creating the Flat Field Correction file, it is necessary to illuminate the CCD with a light pattern that is as representative of the background illumination as possible. This illumination should be bright enough, or the exposure made long enough, so that the CCD pixels signals are at least 25 percent of full scale (for 12-bit mode the level should be at least 1000 ADUs).

Applicable Products: Bobcat cameras

Topic: Flat Field Correction

Keywords: FFC, Flat Field Correction; Shading,

The camera speed (frame rate) depends on the CCD “read-out” time – the time necessary to read all the pixels out of the CCD imager. The frame rate can be calculated using the following Formula 1.1:

Frame rate [fps] = 1 / read-out time [sec] (1.1)

The user can program the camera to run slower than the nominal speed preserving the camera full resolution. The user can independently extend the camera line time (the time required to read one line out of the CCD imager) and camera frame time (the time required to read the entire frame out of the CCD imager). The camera line time can be extended to ~ 200 us, with a precision ~ 25 ns. The camera frame time can be extended to ~ 16 sec, with a precision of ~ 1.0us.

Applicable Products: Bobcat cameras

Topic: Camera Speed (Frame Rate)

Keywords: Speed, Frame Rate, Read-Out Time

The camera can be set to automatic gain (and exposure) control in order to keep the same image brightness during changing light conditions.

In this mode the user sets the image brightness (luminance) to be maintained, and the camera adjusts the gain accordingly. The user can also select the average or peak brightness to be maintained.

The camera starts with changing the gain within the preset by the user min-max limits. If one of the gain limits has been reached, the camera indicates the limit has been reached and keeps the value until the light condition change. The speed of convergence (how fast the camera stabilizes after change), can be preset by the user (four possible options are available).

If both modes, automatic exposure and automatic gain are enabled simultaneously, the camera starts with changing the exposure first within the preset by the user min-max limits. If one of the exposure limits has been reached, the camera engages the analog gain, and changes it within the preset by the user min-max limits.

The AGC algorithm samples all pixels for the entire frame, but the user can select only a portion of the image (AOI) to be used as a sample collecting region. The camera displays the current luminance, current exposure and current gain.

For auto exposure control refer to Automatic Exposure Control (AEC) section.

Applicable Products: All cameras

Topic: Analog gain control

Keywords: Automatic gain control, AGC

On Semiconductor, a supplier of CCD image sensors to Imperx, is adopting a new Color Filter Array (CFA) materials for all its color interline CCD image sensors. This new CFA materials (Gen 2 CFA materials) provides reduced color crosstalk and better color fidelity with only minor changes to the spectral characteristics as shown in the curves below.

Customers may find that adjustments to the color correction matrix coefficients (from those used with current Imperx camera) is required for best color performance.  An application note from On Semiconductor is attached and provides an example of how the color correction matrix coefficients can be adjusted, if desired.

Applicable Products: Bobcat cameras

Topic: Gen2 Color Sensors

Keywords: Generation 2, Gen2, Color, Truesense, Bayer, Filter Material, CFA

Vertical Binning is done in the time domain, where the data from the binned lines is added in the CCD. The vertical binning is performed first, and the vertical AOI is second. The vertical AOI settings are referenced to the binned image. If the user wants to set a vertical window of 200 lines, the user has to put 200 in the AOI height register regardless of the selected vertical binning mode.

Horizontal Binning is done in the digital domain, where the data from the binned pixels is added digitally. The horizontal binning is performed first, and the horizontal AOI is second. The horizontal AOI settings are referenced to the binned image if the user wants to set a horizontal window in the binned image with width 200 the user has to put 200 in the AOI width register regardless of off the selected horizontal binning mode.

Applicable Products: Bobcat cameras

Topic: Vertical versus Horizontal Binning

Keyword: Vertical, Horizontal, Binning