Glossary

Explore a comprehensive list of key terms and definitions related to optical solutions, display technologies, and aerospace & defense innovations.

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A

AMLCD
Active matrix liquid crystal displays (LCD and AMLCD are at Cevians synonomous)
AOI
Angle of incidence. Usually refers to angle of incident light or viewing angle
APSL
Approved Process Supplier Listing
AR Coating
Anti‐reflection coating. A thin layer of transparent material that reduces specular reflection by intereference phenomena due to specific thickness control and different index of refraction
AR Material
As required material are materials that are on the bill of material, are part of the product, that means customers receives it as part of the product but their quantity is not controlled or defined on the bill of material
ATP
Acceptance test procedure. A detailed test document with methods and criteria that is used to inspect and test product before acceptance by quality assurance

B

Backlight
The light source providing illumination to the back of the LCD, using a long narrow PCBA populated with LED's and having a single connector
Bezel
Either refers to the thin sheet metal structure surrounding an LCD in an LCD module OR the aluminum structure in a DHA
Black Mask
Usually refers to a thin black layer of ink that blocks light. It might be part of a touchscreen, EMI glass or heater
BOM
Bill of Material or parts list
Burn‐in
A number of environmental tests that usually include temperature cycling. It is used to detect premature failure of electrical components and the integrity of the product. May also refer to a static image that is visible on LCD screen.

C

CAPA
Corrective Action Preventative Action. A process to address non‐conformance, investigate the root cause, define corrective actions and preventative actions.
CDA
Compressed Dry Air having a pressure dew point 18°F / 10°C below the lowest temperature the system would encounter, but not higher than 35°F
CDR
Critical Design Review closes the critical design phase of the project
Chemfilm
Refers to chemical treatment of aluminum after machining. The treatment results in a microscopic film that is either transparent or yellow/gold. It is a corrosion inihbitor and required on all aluminum surfaces.
Cap Filter
A small glass or polymer optical filter that fits over an LED (Light Emitting Diode) to filter or absorb particular wavelengths
Chromaticity
Means color; generally refers to the color gamut and color integrity of an LCD
Coating
Usually refers to transparent thin film coatings on NVIS filters, EMI glass, Anti-reflective glass or heater glass
COC
Certificate of Conformance is a document certified by a competent authority that the supplied good or service meets the required specifications
Consumables
Materials that are being consumed on the manufacturing floor for the manufacturing of products but are not part of the product itselves. Gloves, clean products, wipes
COO
Certificate of Origin attests that the product listed therein has met certain criteria to be considered as originating in a particular country.
COTS
Commercial off the Shelf. Term for commercial items, including LCD Displays available in the commercial marketplace
CRM
Customer Relation Management. Strategies or software that enable a company to organize and optimize its customer relations

D

DBEF and BEF
Dual brightness enhancement and Brightness enhancement films; Thin prismatic films used behind an LCD to recirculate light in the backlight, increase light output
DHA
Display Head Assembly. An added value product that includes aluminum structure, usally with keys and rotary components and integrating an LCD
DIB
Display Interface Board. It is a PCBA, PWBA that is used to manage the video and power to the LCD
Diffuse
Refers to light dispersion on or through a material
DIP
Detailed Inspection Plan. Detailed information on what to inspect on a part
Drybond
Refers to a bonding process consisting of pressure and vacuum in a semi‐automated equipment, inside a clean‐room

E

ECC
Engineering Change Commitment
ECO
Engineering Change Order
ECR
Engineering Change Request
EMI
Electromagnetic interference. External electrical radiation that can cause disruption of LCD’s and electronics. Generally, EMI is filtered by a clear glass coated with a transparent metallic thin film, ITO and perimeter bus bar.
EMC
Electromagnetic compatibility
ERP
Enterprise Resource Planning software. Cevians uses Made 2 Manage.
ESD
Electrostatic discharge
E3
Electromagnetic Environmental Effects

F

FAI
First Article Inspection. Detailed inspection performed on first parts produced to assess compliance.
FAIR
First Article Inspection Report
FAT
Final Acceptence Test
Flex
Can mean the flexible electrical connection between an LCD PWBA and the LCD glass OR a flexible connection from a touchscreen glass and, or the PWB material of some LCD backlight
FOD
Foreign object debris refers to loose particles that can be introduced or are inside an assembly. Potential risk of electrical contact, visual or mechanical defect.
FPGA
Field Programmable Gate Array. An electronic component in which firmware is installed. Similar to a micro processor
FQE
Field Quality Engineer
Frit
Frit material refers to a high temperature process that fuses a metallic material with glass surface

G

Gamut
Term that refers to the color spectrum achievable by an LCD. It is defined by the coordinate of the red, green and blue color in CIE diagrams 1931 and CIE diagrams 1976

H

HUD
Heads Up Display; operates via a projector to display data from sensors and other sources onto a windshield in a vehicle, aircraft. HUD’s are also used in near eye applications for Virtual Reality (VR) and Augmented Reality (AR) applications
Heater
Means a transparent flat glass with an ITO coating which is terminated on two of its edge with a conductivet bus bar. Heater usually has wires soldered on bus bar to provide electrical contact to the ITO film
Helicoils
Stainless steel spring like device installed in machined aluminum holes. It is used to allow simple and reeated installation of stainless steel screws in an aluminum structure

I

IAT
Internal Acceptence Test
IP
Intellectual Property
IPS
In plane switching, refers to a specific LCD design construction. An IPS LCD will be normally black, cannot see through unless powered. It has large viewing angle, i.e. no color shift of image
ITO
Indium tin oxide. Material used in the transparent layers for EMI and Heaters
Illuminate
In LCD’s and other types of electronic displays, LED backlights are used to illuminate the display as the liquid crystals do not emit light

J

JO
Job Order

K

Kan Ban
A process of automated material demand management. Kan Ban caards are used to trigger additional material demand

L

Laminar Flow
Laminar flow means that the displacement of air, air flow is such that it is structured and layered, no turbulence. (Laminar flow benches are dust controlling benches that have a ventilation system with EPA filters, insuring clean air in the working space)
Lamination
Refers to the bonding process of combining two or more layers of materials to improve structural integrity or to improve optical properties
LCD
Liquid crystal displays
LCD module
an assembly that includes the mechanical structure, an LCD, LED backlight, LGP, optical films and moldframe
LED
Light emitting diode
LGP
Light guide plate. An LCD component used to pipe and distribute light behind the LCD
LVDS
Low‐voltage differential signaling. It is the electrical characteristics on how the information is transmitted to the LCD

M

Mold Frame
An internal structure inside an LCD module that serves as a mechanical support to maintain the LCD in position along with optical films
MRB
Material Review Board. A meeting that invites a number of different functional group. Engineering, Quality, manufacturing to review a defective product and make a decision on its disposition
MURA
A phenomena visible on an LCD that appears as glow mark. This results from variation in the distance between the 2 LCD glass. The cell gap being different, the liquid crystal behavior is altered. In general, this is caused by mechanical stress
MFD
Multi-function Display
MTBF
Mean Time between failures; refers to the longevity of electronic or mechanical component or system

N

N.I.S.T.
National Institute of Standards and Technology. Provides support by continually improving the U.S. measurement system, developing new technologies, fostering standards, and providing both the business and technical evaluation tools needed to produce quality products and organizations
NCR
Non‐conformance report. A formal document detailing the information of a product or component not meeting requirements.
NPI
New Product Introduction. Usually refers to a product that is in development and is being worked on before it is introduced into low rate production Volume
NVIS
Night vision imaging system. Includes elements such as lighting, displays and keypads that operate with Night Vision Goggles (NVG’s). Here used has general reference that means that the light sources are filtered to meet certain military requirements
NVG’s
Devices used to amplify ambient light and improve visibility in low-light or dark conditions
NIR
Near Infrared (NIR) energy is the area of the electromagnetic spectrum from 700 to 2500 nm; NVG’s use NIR energy to enhance images in low light and dark conditions
NIT
A unit of luminance used to measure brightness of a display; equivalent to one candela per meter squared (cd/m2)

O

OCA
Optically Clear Adhesive
OOT
Out of Tolerance. Some calibration point(s) failed to meet the required tolerance level
OSHA
Occupational Safety and Health Administration

P

PFD
Primary Flight Display refers to a digital instrument in the cockpit that presents essential flight information to the pilot
PCAP
Projective capacitive touchscreen
PCB
Printed Circuit Board
PDR
Preliminary Design Review
Pixel
A dot of information on an LCD screen (composed of 3 subpixel, RGB, red green and blue)
PM
Preventative Maintenance
PMR
Preliminary Material Review
PO
Purchase Order
Polarizer
Usually refers to front or back film that polarizes the light linearly on the LCD
PPE
Personal Protective Equipment
PRR
Product Readiness Review
PWB, PCB
Printed wiring board, printed circuit card. Raw card with circuitry but without components
PCBA
Assembled electronic PWB, PCB. Finished electronic card with all its components installed

Q

QE
Quality Engineering
QMS
Quality management system
QP
Quality procedure. Refers to document in our quality management system
Quarantine
Refers to material that needs to be segregate from other production material due to non‐conformance or potential non conformance

R

Radiance
Emission of light. Refers to the amount of light energy in the visible and Near Infrared (NIR) Spectrum that causes sensitivity of night vision goggles. Establish if the emitted light is compatible to be used with night vision Goggles.
Resistive Touchscreen
Touchscreen having two layer of conductors seperated by an air gap. When pressed on the conductive layers are brough closer together changing local resistance resulting in a touch
RMA
Return Material Authorization. A Product that is delivered by a vendor and is being returned for non‐conformance, investigation or out of warranty repair.
RMRA
Risk Management Readiness Assessment
RoHS
Is a regulation regarding the content of hazardous materials. Frequent in electronic assemblies
Row and Column Driver
Electronic chip on the LCD that manages the signal from the DIB and provide signal to all the subpixel TFT
RTV
Return to vendor. Material, usually defective that needs to be returned to a vendor for credit, repair or replacement
RTV
Room temperature vulcanization material. Typically a silicone based material used to seal or bond components
Ring Filter
A glass or polymer filter that fits over an Led to filter or absorb particular wavelengths

S

SDS
Safety Data Sheet
SOP
Standard Operating Procedure. A document provide information on general practice or method on how to use an equipment or tools
Sub‐pixel
A sub‐element, red green or blue of a pixel
Sunlight Readability
Characteristics of an LCD, LCD module or DHA that means the LCD displayed information will be legible in high light environment
SVR
Liquid adhesive used to optically bond heater, EMI, touchscreen or LCD to one another

T

TFT
Thin film transistor, this is the core component of subpixels in an LCD
TN
Twisted Nematic, refers to a specific LCD construction. A TN LCD will be normally white, light can go through when not powered. A TN has high transmission than an IPS
Transmission
Refers to the percentage of light that can go through a media: LCD, EMI, Heater, LGP
T&C
Terms and Conditions
Thermal Loading
For displays used in direct sunlight or high temperature conditions, thermal loading can affect display performance resulting in degraded image quality

U

UV Cure
ultraviolet light used to cure an adhesive

W

WI
Work instruction. Detailed information on a product should be assembled, including pictures and process step
WIP
Work in Progress